vmacair V900137 Underhood70 Air Compressors Owner’s Manual

: June 15, 2024
: vmacair

Table of Contents

vmacair V900137 Underhood70 Air Compressors
Product Information
Important Safety Notice
Safety Messages

vmacair V900137 Underhood70 Air Compressors

Product Information

Specifications

Model: V900137
Website: www.vmacair.com

Installation Manual for VMAC System

This manual provides detailed instructions for the installation of the VMAC System.

VMAC Technical Support

Contact VMAC Technical Support at 888-241-2289 for any assistance or inquiries.

VMAC Knowledge Base

Visit the VMAC Knowledge Base at kb.vmacair.com for additional information and resources.

Changes and Revisions

Revision	Revision Details	Revised by	Implemented
A	Initial release	MSP	17 Apr. 2020
B	ECN: 20-067 Add note on shutdown timer	MSP	11 Jun. 2020
C	ECN: 23-173 Cap Model Year	MSP	16 Aug. 2023

Additional Application Information

Refer to the VMAC Knowledge Base article EXT-VR-003 for more information on timers.

Registered Trademarks

All trademarks mentioned in this manual are the property of their respective owners. VMAC’s use of manufacturers’ trademarks in this manual is for identification purposes only and does not imply any affiliation or endorsement of said companies.

Important Information

Notice: This manual is printed in Canada.

Safety

Important Safety Notice

Only follow proven service procedures recommended in this manual. Anyone deviating from these instructions must ensure that safety is not compromised and that there will be no adverse effects on the equipment’s operational safety or performance. VMAC will not be held responsible for any liability, damages, injuries, loss, or damage to individuals or equipment resulting from failure to adhere to the procedures outlined in this manual or standard safety practices. Safety should always be the top priority when performing any service operations. If you have any questions or need more information, please contact VMAC Technical Support before starting work.

Safety Messages

This manual contains various warnings, cautions, and notices that must be observed to reduce the risk of personal injury during installation, service, or repair. Failure to follow these instructions may result in damage to the equipment or render it unsafe. The following symbols are used:

Attention Symbol: This symbol indicates important safety precautions. Pay attention to the message following this symbol as it concerns your personal safety. Be aware of the possibility of personal injury or death.
Procedure Symbol: This symbol highlights specific procedures that, if not followed, may damage or reduce the useful life of the compressor or other equipment.
Additional Instructions Symbol: This symbol draws attention to additional instructions or special emphasis on a specific procedure.

Warranty

VMAC offers a Standard Warranty (Limited) for their products.
For complete warranty information, including requirements for both the VMAC Standard Warranty (Limited) and VMAC Lifetime Warranty (Limited), please refer to the current published warranty available at www.vmacair.com/warranty.

FAQs

Q: Where can I find more information on timers?

A: You can find additional information on timers in the VMAC Knowledge Base article EXT-VR-003.

70 UNDERHOOD TM AIR COMPRESSORS
Installation Manual for VMAC System
V900137
2020 2023 GM 2500 3500 Pickup, 3500 Chassis Cab 6.6 L Gas (L8T)
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Document: 1930426 Changes and Revisions

Revision

Revision Details

A

Initial release

B

ECN: 20-067 Add note on shutdown timer

C

ECN: 23-173 Cap Model Year

Revised by
MSP MSP MSP

Checked by Eng.
Tech. Qual. Mech. Elec. MCA ASE JWL AWM N/A ASE MSP N/A N/A N/A MSP N/A

Implemented
17 Apr. 2020 11 Jun. 2020 16 Aug. 2023

Additional Application Information
· 2020 2023 GM 2500 3500 Pickup 6.6 L Gas (L8T). · 2020 2023 GM 3500 Chassis Cab 6.6 L Gas (L8T). · Vehicles with push button ignition may be equipped with automatic shutdown
timers. See VMAC Knowledge Base article EXT-VR-003 for more information.

Registered Trademarks
All trademarks mentioned in this manual are the property of their respective owners. VMAC’s use of manufacturers’ trademarks in this manual is for identification of the products only and does not imply any affiliation to, or endorsement of said companies.
Loctite®, Loctite® 242 and Loctite® 567 are registered trademarks of Henkel AG & Company KGaA. Nylok® is a registered trademark of Nylok Fastener Corporation. Eaton Aeroquip® is a registered trademark of EATON AEROQUIP INC. GM®, and GMC® are registered trademarks of General Motors Company LLC.

Important Information
The information in this manual is intended for certified VMAC installers who have been trained in installation and service procedures and/or for anyone with mechanical trade certification who has the tools and equipment to properly and safely perform the installation or service. Do not attempt installation or service without the appropriate mechanical training, knowledge and experience. Follow all safety precautions. Any fabrication for correct fit in modified vehicles must follow industry standard “best practices”.

Notice
Copyright © 2021 VMAC Global Technology Inc. All Rights Reserved. These materials are provided by VMAC for informational purposes only, without representation or warranty of any kind, and VMAC shall not be liable for errors or omissions with respect to the materials. The only warranties for VMAC products and services are those set forth in the express warranty statements accompanying such products and services, if any, and nothing herein shall be construed as constituting an additional warranty. Printing or copying of any page in this document in whole or in part is only permitted for personal use. All other use, copying or reproduction in both print and electronic form of any part of this document without the written consent of VMAC is prohibited. The information contained herein may be changed without prior notice.
Printed in Canada

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Safety

Important Safety Notice
The information contained in this manual is based on sound engineering principles, research, extensive field experience and technical information. Information is constantly changing with the addition of new models, assemblies, service techniques and running OEM changes. If a discrepancy is found in this manual, contact VMAC Technical Support prior to initiating or proceeding with installation, service or repair. Current information may clarify the issue. Anyone with knowledge of such discrepancies, who proceeds to perform service and repair, assumes all risks.
Only proven service procedures are recommended. Anyone who departs from the specific instructions provided in this manual must first ensure that their safety and that of others is not being compromised, and that there will be no adverse effects on the operational safety or performance of the equipment.
VMAC will not be held responsible for any liability, consequential damages, injuries, loss or damage to individuals or to equipment as a result of the failure of anyone to properly adhere to the procedures set out in this manual or standard safety practices.
Safety should be the first consideration when performing any service operations. If there are any questions concerning the procedures in this manual, or more information is required, please contact VMAC Technical Support prior to beginning work.
Safety Messages
This manual contains various warnings, cautions and notices that must be observed to reduce the risk of personal injury during installation, service or repair and the possibility that improper installation, service or repair may damage the equipment or render it unsafe.
This symbol is used to call attention to instructions concerning personal safety. Watch for this symbol; it points out important safety precautions, it means, “Attention, become alert! Your personal safety is involved”. Read the message that follows and be aware of the possibility of personal injury or death. As it is impossible to warn of every conceivable hazard, common sense and industry standard safety practices must be observed.
This symbol is used to call attention to instructions on a specific procedure that if not followed may damage or reduce the useful life of the compressor or other equipment.
This symbol is used to call attention to additional instructions or special emphasis on a specific procedure.

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Warranty

VMAC Standard Warranty (Limited)
For complete warranty information, including both VMAC Standard Warranty (Limited) and VMAC Lifetime Warranty (Limited) requirements, please refer to our current published warranty located at: www.vmacair.com/warranty

If you do not have access to a computer, please contact us and we will be happy to send you our warranty.

VMAC’s warranty is subject to change without notice.

VMAC Lifetime Warranty (Limited)

A VMAC Lifetime Limited Warranty is offered

AIR INNOVATED

on the base air compressor only and only on

UNDERHOODTM, Hydraulic Driven, Transmission Mounted, Gas and Diesel Engine Driven Air

LIFETIME

Compressors, Multifunction Power Systems, and other products as defined by VMAC, provided that (i) the purchaser fully completes and submits a

WARRANTY
TRUST SERVICE VALUE

warranty registration form within 3 months of purchase, or 200 hours of operation,

whichever occurs first; (ii) services are completed in accordance with the Owner’s

Manual; (iii) proof of purchase of applicable service kits are made available to

VMAC upon request.

The VMAC Lifetime Warranty is applicable to new products shipped on or after 1 October, 2015.

Warranty Registration

The VMAC warranty registration form is located near the back of this manual. This warranty registration form must be completed and sent to VMAC at the time of installation for any subsequent warranty claim to be considered valid.

There are 4 ways the warranty can be registered with VMAC:

www.vmacair.com/warranty

warranty@vmacair.com
877-740-3202 VMAC – Vehicle Mounted Air Compressors 1333 Kipp Road, Nanaimo, BC, Canada V9X 1R3

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VMAC Warranty Claim Process
VMAC warranty work must be pre-authorized by VMAC. Claims are processed via our dealer network. If you are not a VMAC dealer, please select one to work with via our Dealer Locator: https://www.vmacair.com/dealer-locator/
1. Communicate with VMAC Technical Support at 1-888-241-2289 or tech@vmacair.com to help diagnose/troubleshoot the problem prior to repair. VMAC technical support will require the VMAC System ID, hours on the compressor and mileage on the vehicle.
2. VMAC will provide direction for repair or replacement of the failed components.
3. If requested, failed parts must be returned to VMAC for evaluation.
4. Dealers may login to the VMAC website to view the “VMAC Labour Time Guide” (under “Agreements”) to see the allowable warranty labour times.
5. Warranty invoices must include the Service Ticket number, VMAC System ID#, hours on the compressor, and a detailed description of the work performed.
6. VMAC Warranty does not cover consequential damages, overtime charges, mileage, travel time, towing/recovery, cleaning or shop supplies.
7. Dealers submit warranty claims on behalf of the Vehicle Owner/End User affected by the defective part(s). The dealer ensures that all warranty credits are refunded back to the Vehicle Owner/End User who made the initial warranty claim. In order to qualify for Lifetime Warranty (Limited), the completed warranty registration form must be received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, whichever occurs first. If the completed warranty registration form has not been received by VMAC within 3 months of the buyer receiving the Product(s), or 200 hours of operation, the warranty period will be deemed to commence 30 days from the date of shipment from VMAC. Failure to follow the warranty claim process may result in denial of the warranty claim.
VMAC Product Warranty Policies & Warranty Registration can be found on the VMAC website (see previous page for URL).

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General Information

Optional Equipment Compatibility
While VMAC strives to design systems compatible with optional OEM equipment (such as running boards), it is impractical to develop systems that accommodate every OEM and aftermarket option or add-on. Whenever possible, VMAC endeavors to advise of compatibility issues in the “Additional Application Information” section of the manual. Even when specific optional equipment is determined by VMAC to be incompatible, it does not preclude the vehicle upfitter or end user from modifying the optional equipment to make it compatible with the installed VMAC system. VMAC does not warranty or accept responsibility or liability for the fitment, function or safety of any products modified in any way not expressly outlined in the installation manual.
Before Starting
Note and label all parts that are removed from the vehicle as many of the OEM parts will be reused during the installation of the VMAC system.
Read this manual prior to beginning the installation to ensure familiarity with the components and how they will fit on the vehicle. Identify any variations from the application list such as vehicle model, engines, or optional equipment (e.g., dual alternator, active steering assist, etc.).
Open the package, unpack the components and identify them using the Illustrated Parts List (IPL) included in the Fastener Pack.
Hose Information
Depending on other installed equipment, it might be necessary to move the air/oil separation tank from its intended location. The hoses used in VMAC compressor systems have a specific inner liner that is compatible with VMAC compressor oil. Use of hoses other than those supplied or recommended by VMAC may cause compressor damage and may void your warranty. Please contact VMAC for replacement hoses and further information.
Ordering Parts
To order parts, contact a VMAC dealer. The dealer will ask for the VMAC serial number, part number, description and quantity. Locate the nearest dealer online at www.vmacair.com/dealer-locator or call 1-877-912-6605.

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Special Tools Required
· GM flywheel locking tool P/N: J42386-A. · Pneumatic fan wrench removal set (such as Lisle® 43300) or a manual fan
pulley holder (such as KD Tool® KD3900).
· Pulley removal tool kit (such as a Lilse 39000, Jet H3565 or Performance Tool
389708 or equivalent).
· Optional: GM specialty tool P/N: J45059 (Angle meter).
Torque Specifications
All fasteners must be torqued to specifications. Use manufacturers’ torque values for OEM fasteners.
The torque values supplied in Table 1 are intended for VMAC supplied components, or for use as a guide in the absence of a torque value provided by an OEM.

Apply Loctite 242 (blue) to all fasteners (except nylon lock nuts) unless otherwise stated.

Torque values are with Loctite applied unless otherwise specified.

Standard Grade 8 National Coarse Thread

Size (in)

1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4

Foot pounds (ft·lb) 9 18 35 55 80 110 170 280

Newton meter (N·m) 12 24 47 74 108 149 230 379

Standard Grade 8 National Fine Thread

Size (in)

3/8

7/16

1/2

5/8

3/4

Foot pounds (ft·lb)

40

60

90

180

320

Newton meter (N·m) 54

81

122

244

434

Size (mm)

Metric Class 10.9

M6

M8

M10

M12

M14

M16

Foot pounds (ft·lb) 4.5

19

41

69

104

174

Newton meter (N·m)

6

25

55

93

Table 1 — Torque Table

141

236

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Preparing for Installation

Preparation for installation is very important. Missing a step or an item can cause problems in the installation or damage to components.
Check off each item as it is completed so that no steps are
missed.
When dissembling engine components, cover the openings to prevent debris from entering the system.
Apply Loctite 242 (blue) to all fasteners (except nylon lock nuts) unless otherwise stated.
Review the contents of the system using the illustrated parts list to ensure all
components are present and in the correct quantity. If any components are missing, have the system ID ready and call VMAC Technical Support.
Disconnect the battery. Remove the lower bumper/air dam to improve access. Drain the coolant into a clean container and set the coolant aside for use later. Remove the passenger side running board (if applicable). Remove the air filter housing, air intake tube and resonator box. Remove the upper fan shroud. Remove the upper radiator hose. Remove the fan stator. Remove the fan. Remove the lower fan shroud. Remove the main Front End Accessory Drive Belt (FEAD) belt (Figure 1).
Main FEAD belt

Figure 1 — Remove main FEAD belt (dual alternator configuration shown)

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Remove the passenger side inner fender. Remove the lower radiator hose. Remove the pulley from the power steering pump.
Do not remove the power steering fluid lines from the power steering pump.
Unbolt the power steering pump and secure it out of the way (Figure 2).

Figure 2 — Shift power steering pump out of the way
Dual alternator systems only: Remove the secondary alternator (Figure 3).

Figure 3 — Remove the secondary alternator

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Dual alternator systems only: Remove the upper idler on the power steering
bracket to access the bracket fastener located behind it (Figure 4).

Figure 4 — Dual alternator bracket
Remove the power steering bracket (Figure 4 or Figure 5).

Figure 5 — Single alternator bracket

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Dual alternator systems only: Press the bushings out of the power steering
bracket.
Remove the harness from the cable management bracket (Figure 6).
Cable management bracket

Figure 6 — Remove cable management bracket
Remove the cable management bracket (Figure 6). Detach the harness from the cable anchors running along the top of the valve
cover, and secondary battery box (Figure 7).

Valve cover harness

Secondary battery box

Figure 7 — Remove harness from cable ties

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Remove the cable tie anchor from the harness running from the underside of the
engine block (Figure 8).
Remove cable tie
Figure 8 — Detach harness

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Installing the Main Bracket
Apply Loctite 242 (blue) to all fasteners (except nylon lock nuts) unless otherwise stated.
Using the supplied flat head fasteners, install the steel bracket onto the rear of
the VMAC main bracket (Figure 9).
Figure 9 — Mount steel bracket to VMAC main bracket
Dual alternator systems only: Press the OEM alternator mount bushings into
the VMAC main bracket (Figure 10).

Figure 10 — Install OEM bushings

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Use care when installing the VMAC main bracket to ensure the hoses and/or wire harnesses are not pinched.
Install the VMAC main bracket onto the engine (Figure 11).

(×3) OEM fasteners

M8×1.25×25

M8×1.25×120

M8×1.25×70

Figure 11 — Install main bracket
Secure the engine harness and PCV hose away from the rear of the VMAC
bracket to prevent wear or abrasion (Figure 12).

Harness and PCV
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Figure 12 — Secure harness and PCV hose
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Using the supplied P-clip and M8 nut, secure the heat shielded harness to the
engine (Figure 13). Secure harness to engine
Figure 13 — Secure heat shielded harness
Using the supplied harness anchors, resecure the harness to the top of the
engine and battery box (Figure 7 on page 11). Use care when installing the power steering pump to ensure there is no strain put on the hoses
Using the OEM fasteners, install the power steering pump (Figure 14).

Figure 14 — Install power steering pump

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Ensure the power steering pump hard line is not contacting the VMAC main
bracket (Figure 14).
Dual alternator systems only:
Install the OEM idlers onto the VMAC main bracket. *Using the OEM fasteners, install the alternator onto the VMAC main
Bracket.
Install the power steering pump pulley. Install the OEM FEAD belt

Figure 15 — OEM FEAD belt (single alternator)

Figure 16 — OEM FEAD belt (dual alternator)

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Install the VMAC FEAD bracket (Figure 17).

M8×1.25×70

M8×1.25×50
Figure 17 — Install VMAC FEAD bracket Use care when installing the VMAC FEAD bracket to ensure the power steering hard line is not contacting either of the VMAC brackets. If necessary, gently deflect the hard line to provide clearance.
Ensure the tensioner and idlers are torqued to specification. Remove the inlet valve from the compressor and cover the opening to prevent
debris entering the compressor.

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Install the compressor onto the main bracket (Figure 18).

Figure 18 — Install compressor
The inlet valve is secured with bolts of varying lengths. Installing the bolts in the wrong location will damage the compressor housing when tightened.
Remove the protective covering and reinstall the Viton® O-ring and inlet onto
the compressor (Figure 19).

M8×1.25×50

M8×1.25×55

M8×1.25×75

Figure 19 — Install inlet

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Apply loom to the coolant drainback hose where it will contact the inlet. Route the coolant drainback hose below the inlet (Figure 20).
Coolant reservoir hose
Coolant drainback hose
Figure 20 — Install inlet
Route the coolant reservoir hose over the inlet (Figure 20).

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Installing the VMAC Crank Pulley
Remove the starter motor and install the OEM flywheel locking tool (GM P/N:
J42386-A.)
Inspect the face of the OEM pulley and remove any surface burrs to ensure
there is a clean mating surface for the VMAC crank pulley.
Place the VMAC crank pulley in position over the OEM pulley. Ensure that it fits
flat against the OEM pulley. Liquid Loctite 242 must be used to achieve correct torque on the crankshaft bolt as it functions as a thread lubricant, as well as a locking compound. Solid or Stick Loctite cannot be used.
Completely coat the threads with Loctite 242 (blue) and install the supplied
VMAC crankshaft bolt and washer finger tight (Figure 21.
Completely coat threads with Loctite 242
Figure 21 — VMAC crank pulley bolt
Rotate the VMAC crank pulley counterclockwise until the lugs on the back
of the pulley are tight against the OEM pulley spokes and tighten the bolt sufficiently to hold the pulley in position Figure 22).

Figure 22 — Engage VMAC crank pulley lugs on OEM pulley

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Ensure the VMAC crank pulley does not move off of the OEM pulley face before tightening the pulley bolt. Ensure the pulley is rotated tight against the pulley lugs.
Do not use an impact tool to tighten the pulley bolt
Torque the VMAC crank pulley bolt as per GM specifications. The GM specifications as of 6 April 2020:
1.) Torque to 89 ft·lbs (120 N·m).
2.) Loosen 360°.
3.) Torque to 59 ft·lbs (80 N·m).
4.) Turn an additional 125°. *Angle can be measured with GM P/N: J 45059: Angle Meter
Remove the OEM flywheel locking tool and reinstall the starter motor. Install the VMAC belt (Figure 23).

Figure 23 — VMAC belt routing

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Modifying the Hoses and Installing the Cooler
On the quick connect side of the lower radiator hose, cut the hose square, just
before the first bend (Figure 24).

Figure 24 — Modify lower radiator hose
From the engine side of the hose, measure 8 1/2 in along the outside radius and
cut the hose square (Figure 25).
8 1/2 in

Figure 25 — Modify lower radiator hose

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Using the supplied gear clamps, install the modified hoses onto the cooler (note
that the hose with the quick connect goes on the side of the cooler with the plug) (Figure 26).

Figure 26 — Assemble cooler
Remove the rear brake line anchor from the passenger side upper control arm
mount (Figure 27).

Remove brake line
anchor

Figure 27 — Shift brake line

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Pull the forward brake line anchor out of the frame to allow the brake line to be
shifted (Figure 28).
Remove brake line
anchor
Figure 28 — Shift brake line Use care when installing the inner bracket to prevent kinking or damaging the brake line.
Using the supplied fasteners, install the (×2) brackets onto the passenger side
frame rail with the brake line passing over top of the inner bracket (Figure 29, Figure 30).

Figure 29 — Install cooler bracket

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Figure 30 — Install cooler bracket
Rotate the front brake line anchor 180° (shifting the brake line approximately
1 in toward the inside of the frame rail) and reinsert it into the frame (Figure 31).

Figure 31 — Install cooler bracket

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Using the supplied P-clip and fastener, secure the brake line to the stud in the
cooler bracket (Figure 32).
Figure 32 — Install cooler bracket
Slide the cooler and hose assembly into place on the bracket and connect the
quick connect to the radiator (Figure 33).

Figure 33 — Install cooler
Install the mounting bolts and nuts and torque them to specification (Figure 33). Connect the remaining cooler hose to the engine (Figure 33).

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Installing the Air Oil Separator Tank (AOST)
Dependent upon other installed equipment, it may be necessary to move the AOST from its intended location. The hoses used in VMAC compressor systems have a specific inner liner that is compatible with VMAC compressor oil. Use of hoses other than those supplied or recommended by VMAC may cause compressor damage and may void the warranty.
The AOST must be level for proper air/oil separation, and to ensure that the oil level will display accurately in the sight glass.
Apply Loctite 242 (blue) to all fasteners (except nylon lock nuts) unless otherwise stated.
Installing the AOST
The AOST will mount to the passenger side frame rail between the 2 forward body mounts (Figure 34).

Front of vehicle

Figure 34 — AOST installed (Pickup chassis shown)

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Pickup Applications

Install the tank mounting brackets on the frame (Figure 35):
· The AOST brackets mount to either side of the transmission crossmember.

(×2) Pinch bolt lock nut

(×4) M10×1.5×130 bolts

Mount to upper pattern

(×4) M10×1.5 flange lock nut
Mount tank to upper holes

(×4) M8×1.25×12
bolts

(×4) 3/8 in washer

(×2) Pinch bolt

Front of vehicle

Figure 35 — Installing the AOST (Pickup) (For clarity, the front AOST mounting hardware is not shown)
Using the (×4) M10×1.5×130 bolts and M10 nuts, install the tank mounts and
backing straps on either side of the transmission crossmember. Leave the bolts finger tight to allow for minor adjustment (Figure 35).
Remove the tank clamp pinch bolts. Install the tank clamps over the front of the tank and slide them toward the
centre of the tank.

Install the tank using the upper bolt pattern of the tank mounts (Figure 35):
Adjust the tank in the straps to bring the rear of the tank close to (but not
touching) the rear cab mount.
*Install the (×2) pinch bolts and nuts into the mounting clamps. Leave the
fasteners finger tight to allow for adjustment when installing the hoses.

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Chassis Cab Applications
Install the tank mounting brackets on the frame (Figure 36):
· The AOST brackets mount to either side of the transmission crossmember.

(×2) Pinch bolt lock nut

(×4) M10×1.5×130 bolts

Mount to lower pattern

(×4) M10×1.5 flange lock nut
Mount to upper pattern

(×4) M8×1.25×12
bolts

(×4) 3/8 in washer

(×2) Pinch bolt

Front of vehicle

Figure 36 — Installing the AOST (Chassis Cab) (For clarity, the front AOST mounting hardware is not shown)
Using the (×4) M10×1.5×130 bolts and M10 nuts, install the tank mounts and
backing straps on either side of the transmission crossmember (position the rear tank mount and backing strap a few inches to the rear of transmission crossmember – just as the flange starts to flare). Leave the bolts finger tight to allow for minor adjustment (Figure 36).
Remove the tank clamp pinch bolts. Install the tank clamps over the front of the tank and slide them toward the
centre of the tank.
Install the tank onto the tank mounts (Figure 36):
Mount the rear tank clamp to the lower bolt pattern. Mount the forward tank clamp to the upper bolt pattern. Adjust the tank in the straps to bring the rear of the tank close to (but not
touching) the rear cab mount.
*Install the (×2) pinch bolts and nuts into the mounting clamps. Leave the
fasteners finger tight to allow for adjustment when installing the hoses.

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Ensure none of the fasteners are touching the AOST or the torsion bar.
Rotate the tank so that the directional arrow on the rear of the tank is pointing
upwards (Figure 37).

Figure 37 — Securing the AOST (Rear view)
AOST orientation is critical. The arrow must be pointing up to prevent compressor failure due to oil starvation, or oil in the discharge air.

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Hose Requirements

Only attempt to shorten the supplied hose if there is access to the appropriate equipment. Do not cut and splice the hose using hose clamps.
VMAC Compressor oil will degrade rubber lined hoses, use only hoses with an AQP elastomer type liner. Contact VMAC Technical Support at 1-888-241-2289 for further information.
The PTFE tubes and AQP elastomer lined hoses are specifically designed to work with VMAC compressor oil and at compressor operating temperatures.
Based on the desired location of the AOST, the hose lengths provided with this system may not be ideal. VMAC suggests first trying to adjust the AOST within its mounts to take up any excess slack in the hoses. If this is not effective, the hoses can be shortened or replaced as necessary, or hose extenders can be used.
VMAC recommends shortening these hoses as a preferred alternative to coiling up and securing the excess. Shorter hose length will maximize system performance.
Avoid using 90° fittings wherever possible as they cause flow restrictions and negatively impact performance.
The following hoses are included with this compressor kit:
· 1/2 in × 56 in. · 1/2 in × 80 in. · 3/4 in × 86 in. · 1/4 in (PTFE Tube) × 130 in. · 3/16 in (PTFE Tube): × 130 in.
If longer hoses are required:
To order parts, contact a VMAC dealer. The dealer will ask for the VMAC serial number, part number, description and quantity. See page 6 for ordering information.
· Eaton Aeroquip hoses with an “AQP” type inner liner are required. · OTC fittings are required for the VMAC supplied hose. · Push-lock fittings are suitable if FC332 hose is used. · If Push-lock fittings are being used, do not use hose clamps as they will
damage the hose and cause leaks.

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Routing and Connecting the Hoses

When routing hoses, ensure cap plugs are installed so that contaminants do not get in the line. Take care when routing hoses, as a hose failure may damage the compressor and/or cause injury.
All hoses, tubes and wires that are installed, rerouted or shifted during the installation must be secured so that they do not contact any hot, sharp or moving parts. Use rubber coated P-clips wherever possible. Follow the routing suggestions in this manual and cover all hoses with plastic loom.

Ensure there is sufficient slack in the hose routing to allow for normal engine movement.

PTFE Tubing, Loom, and Push-To-Connect Fittings
PTFE tubing should only be cut using proper tubing cutters. Side cutters, utility
knives, etc. will deform the tube, preventing a proper seal (or leave sharp edges which cut the internal O-ring).
When applying loom to the PTFE tube, leave approximately 1 in between the
loom and the fitting.
Ensure the tube is clean, cut at 90° and that there are not sharp edges. Lubricate the tube and firmly push it into the fitting so that the tube fully seats
in the fitting.
Slide the collet out, away from the body of the fitting to lock the tubing in place. Ensure the tube does not have any “play” to prevent the O-ring from wearing.

Cut the tube squarely, using only proper tubing cutters as side cutters
will deform the tube.

Slide the collet out once the tube is fully inserted

O-ring

Figure 38 — Push-to-connect fittings

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Apply loom (not supplied) to the 3/4 in and 1/2 in hoses. Connect the 3/4 in discharge hose to the straight fitting on the rear of the
compressor.
Route the discharge hose to the firewall and secure it to the stud using one of
the supplied P-clips and nuts (Figure 39).
P-clip to OEM studs

Figure 39 — Connect discharge hose
Route the discharge hose over the engine, toward the passenger side of the
engine bay, and secure it in place using one of the supplied P-clips and nuts (Figure 39).
Route the discharge hose down, toward the passenger side fender well. Using a
P-clip, bolt, and nut, secure the hose to the tab on the fuse box (Figure 40).
Fuse box tab
Ground strap stud

Figure 40 — Connect discharge hose
Continue routing the discharge hose toward the fender well, securing it to the
ground strap stud using a P-clip and nut (Figure 40).

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Connect the discharge hose to the fitting on the AOST. Using the nut from the body mount, install the suppled bracket (Figure 41).
Install bracket
Figure 41 — Connect discharge hose
Using the supplied P-clip and fasteners, secure the discharge hose to the
bracket (Figure 41).
Connect the 90° fitting on the longer 1/2 in oil supply hose to the forward
fitting on the oil cooler.
Route the hose from the cooler to the subframe and secure it using a P-clip
(Figure 42).

P-clip to subframe

Figure 42 — Route oil supply hose

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Route the 1/2 in oil supply hose along the top of the front (tube) crossmember,
to the driver side of the vehicle and secure it in place using cable ties.
From the crossmember, pass the 1/2 in hose up, between the lower fan shroud
and the frame rail, and connect it to the 90° fitting on the compressor.
Using the supplied P-clip, M4 nut and #6 washer, secure the hose to the ECU
housing (Figure 43).

Figure 43 — Route oil supply hose
Connect the 90° fitting on the shorter 1/2 in oil return hose to the rear fitting
on the cooler.
Route the 1/2 in oil return hose along to top of the frame rail to the AOST. Connect the 1/2 in oil return hose to the AOST.

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Secure the 1/2 in oil return hose to the VMAC discharge hose and the nearby
harness (Figure 44).

Figure 44 — Route oil return hose
Apply the supplied loom to the 1/4 in and 3/16 in PTFE tubes. Connect the PTFE tubes their respective fittings on the inlet. Route the 1/4 in and 3/16 in PTFE tubes along the 3/4 in discharge hose; secure
the tubes to the 3/4 in hose using cable ties.
Trim the PTFE tubes as necessary and connect them to their respective fittings on
the AOST.
Adjust the AOST in the mounts as necessary to provide optimal hose routing. Torque all of the AOST mounts.

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Modifying the Fan Shroud Stator
Remove the (×2) bolt bushings from the passenger side fan stator mounts. From the base of the lower stator mount, measure 2 1/2 in toward the engine
side of the mount and mark the location (Figure 45, Figure 46).
Modify lower stator
Figure 45 — Modify the lower stator mount

2 1/2 in

Figure 46 — Modify the lower stator mount

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From the mark, measure 1/2 in toward the center for the mount (Figure 47).
1/2 in
Figure 47 — Modify the lower stator mount
From the line, mark a line 90° out to the side of the mount (Figure 48).

Figure 48 — Modify the lower stator mount

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Cutting perpendicular to the face of the fan stator rib, remove the marked area
(Figure 49).

Figure 49 — Modify the lower stator mount
Install the fan spacer onto the water pump. Install the fan stator spacers (Figure 50).

Install fan stator spacers

Figure 50 — Install fan stator spacers
Install the lower fan shroud.

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Using the (×2) supplied fasteners, and the longer OEM fastener (into the VMAC
FEAD bracket), install the stator.
Ensure there is 1/4 in clearance between the pulley and the stator mount. An additional clearance may need to be cut on the face of the stator mount (Figure 51).
Verify there is 1/4 in clearance between the VMAC crank pulley and the stator
mount. If required, modify the mount (Figure 51).

Figure 51 — Modify the lower stator mount
Install the fan onto the fan spacer. Install the upper fan shroud. Re-secure the A/C lines using the OEM P-clips, ensuring the A/C lines do not
contact each other, the cooler, or the oil lines.
Install the upper radiator hose and secure it to the VMAC FEAD bracket using
the supplied P-clip and fastener (Figure 52).

Figure 52 — Secure upper radiator hose

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Adding Oil to the System
The VMAC supplied and approved compressor oil must be used in this system. Failure to use this special oil will result in damage to the compressor and will void warranty.
Do not overfill the system. Overfilling the system with oil can flood the sight glass window and make the system appear empty.
Lower the vehicle from the axle-stands. Ensure the vehicle is parked on level ground. Remove the oil filter from the AOST and discard the cardboard warning tag.
Apply a light film of compressor oil to the filter gasket and thread the filter onto the AOST until the gasket makes contact. Tighten the filter an additional 3/4 to 1 turn after the gasket contacts the base.
Remove the cap from the oil-fill port located on the Inlet valve (Figure 53).

Oil fill plug

Figure 53 — Oil fill location
Fill the system with the supplied oil (when dry, the system will take
approximately 5 L (5.2 qt) of oil). Rotate the compressor clutch by hand while adding oil to speed the process. Do not use power tools to rotate the clutch.
Allow a few minutes for the oil to drain into the AOST. Check the level at
the sight glass at the front of the AOST. Continue adding oil until the level is correct.
Replace the oil fill cap and tighten.

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Installing the Control Components

Best Practices
· To confirm a good ground, use an ohm meter to measure the resistance
between the ground point and the negative battery terminal. Resistance should be less than 1 .
· Route all wires to ensure they will not contact hot, sharp or moving parts
(including the park brake mechanism, steering column, and pedals).
· Before drilling any holes ensure there are no OEM wires, hoses, or
components that may be damaged.
· Do not use a test light to probe for power on vehicle circuits, the increased
current draw of the test light may damage components.
· VMAC recommends using only sealed crimp and solder butt connectors for
all electrical connections.
· To ensure a durable connection, use only good quality crimping tools. · Apply loom to all wiring:
Use high temperature loom in areas where high temperatures may be expected.
Use spiral loom in areas with high vibration.
In-line Butt Splice Connections
· Cut the wire approximately 2 in from the connector. · Strip approximately 3/8 in from the end of both sides of the cut wire, as well as
from the end of the wire being spliced in-line.
· Twist the wire to be spliced in-line, together with the “live” side of the wire (not
the wire attached to the connector).
· Slide the butt connector onto the twisted wires and crimp it. · Insert the “connector side” of the wire into butt connector and crimp it. · Lightly tug the wires to ensure they are properly crimped. · Using a heat gun, carefully apply heat to the butt connectors to seal the
connection.
Tying into OEM connectors
Some OEM connectors may have locking tabs that must be disengaged prior to inserting a crimped connector.

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Digital Throttle Control Wire Schematic

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Engine Compartment Pressure Sensor

Compressor

Black 3-Pin Connector

Control Box

Figure 54 — Digital throttle control

Temperature Probe

Clutch wire Black

Bullet Connector

Green 4-Pin Connector

To Ground X260 Aux female connector pin 13 (IGN 12 V)

K9 BCM
X1

Pin 25 Pin 24

Light Blue Grey

To Ground

CAN Converter Module

Blue

Green

Blue Green

Splice to OBD II pin 6, Blue wire with black strip Splice to OBD II pin 14, White wire
Connect to accelerator Pedal
To OEM connector from Accelerator pedal

Light Blue Grey

White 4 – Pin Interface Connector

Red White
Black Green
Red
Red

Bullet Connector

Throttle Control

43

Control Box

Install the control box in a convenient location in the cab (such as the
lower dashboard panel), positioned so that the wire harness will reach the compressor.
Throttle Control
Using cable ties, secure the throttle control under the dashboard, next to the
OBD II port. Ensure it is away from moving parts and positioned so that the buttons and LED lights are accessible.
Connecting the Wiring
Unplug the OEM cable from the accelerator pedal and plug it into the matching
connector from the throttle control. Plug the cable from the throttle control into the matching connector on the accelerator pedal.
Connect the interface harness to the matching connector from the control box. Attach the (×3) green wires with ring connectors, running from the CAN
converter module, the white 4 pin interface connector, and the throttle control, to a good ground under the dashboard.
Locate the OBD II port (generally located under the dashboard, beneath the
steering column).
Remove the fasteners securing the OBD II port to the dashboard; this provides
easier access to the wires at the back.
Peel back the tape on the harness a few inches.
The wires populating pins 6 and 14 of the OBD II port are a twisted pair (blue wire with black stripe and white wire).

Figure 55 — OBD II connector
Splice the light blue wire from the throttle control to the wire at pin 6 (blue wire
with black stripe) of the OBD II port.
Splice the grey wire from the throttle control to the wire at pin 14 (white wire)
of the OBD II port.

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Locate and disconnect the K9 Body Control Module X1 (26 pin “natural” or white
connector) under the driver side dashboard (near the exterior wall).
The wires populating pins 24 and 25 of the K9 Body Control Module X1 are a twisted pair (white wire and blue wire).

4

1

7

14

8

20

15

26 25 24

21

Figure 56 — X260 Auxiliary Instrument Panel
Splice the light blue wire from the CAN converter module to the wire at pin 25
(blue wire) of the X1 module.
Splice the grey wire from the CAN converter module to the wire at pin 24 (white
wire) of the X1 module.
Splice the black wire running from the VMAC 4 pin interface connector to the
black wire on the CAN Converter.
Splice the blue wire running from the throttle control to the blue wire on the
CAN converter module.
Reconnect the X1 connector.

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Locate and disconnect the X260 Auxiliary Instrument Panel Harness (14 pin
light grey connector) under the driver side dashboard (near the exterior wall).

7

1

14 13

8

Figure 57 — X260 Auxiliary Instrument Panel
Insert the terminal from the orange wire (with a terminal on one end and a butt
connector on the other end) into pin 13 of the X260 connector. If pin 13 of the X260 connector is already populated, continue to the next step.
Cut the terminal off of the orange wire and splice it to the existing wire
populating pin 13.
Splice the orange wire to the red wires from the CAN converter module, and the
white 4 pin interface connector.
Using cable ties, secure the CAN converter module in place. Connect the red wire with the bullet connector, running from the control box, to
the matching red wire running from the throttle control. Route the following wires into the engine compartment via a grommet in the firewall:
Grey cable with the green plug connector from the control box. Grey cable with the black connector from the throttle controller. White wire with a bullet connector from the interface cable. Cover all of the engine compartment wires with plastic loom.
Compressor connections
Route the (×2) grey cables and the white wire over to the compressor. Connect the grey cable with the green plug connector to the corresponding
connector coming from the rear of the compressor.
Connect the grey cable with the black connector to the matching connector on
the pressure transducer at the compressor.
Connect the white wire with the bullet connector to the matching connector at
the compressor clutch.
Using one of the supplied P-clips, secure the clutch wire and pressure sensor
harness, along with the coolant reservoir hose, to one of the inlet fasteners.

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Completing the Installation
Reinstall the inner fender liner. Reinstall the air filter housing, air intake tube and resonator box. Reinstall the lower bumper/air dam. Fill the coolant system with the coolant saved earlier. Check all wiring, hoses and tubes to ensure that they will not contact any hot
or moving components and will not interfere with the operation of the vehicle. Ensure all wiring, hoses and tubes are secured with cable ties and protected with loom as required.
Cover all VMAC under-hood wiring with high heat plastic loom (if not done
previously). Secure the harness with cable ties as needed to avoid hot, sharp or moving components.
Pull any excess wiring back into the cab and tie it up and out of the way under
the dash with cable ties.
Re-connect the battery. Reinstall the running boards using the supplied low profile mounting brackets (if
applicable). The System Identification Plate must be attached to the vehicle at the time of installation. This plate provides information that allows VMAC to assist with parts and repairs.
Locate a conspicuous area in the engine bay (where the tag will be easily
noticed) to install the System ID tag.
Mark and drill (×2) 7/64 in holes and secure the plate with the supplied self-
tapping screws (Figure 58).
Figure 58 — System Identification Plate
To alert any technicians that may service the vehicle, affix the servicing
caution/contact label in the engine compartment near the hood latch in a visible location (Figure 59).

Figure 59 — Advisory label

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Install the belt routing label in the engine compartment near the hood latch in
a visible location (Figure 60).
Figure 60 — Belt routing label (actual belt routing label may differ)
As part of the installation process, ensure that the safety and operational
instruction decal is affixed in an obvious location so that it can be seen by vehicle operators. A good spot for this is usually on the inside of the door or on the panel underneath the steering wheel (Figure 61).

Figure 61 — Operating Instruction label

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Recommended Accessories
While the compressor system will function without the following accessories, VMAC strongly recommends their use for optimal performance.
See the “Accessory Product” section of this manual on page 58 for a list of products available for purchase through VMAC.
Receiver Tank
An air receiver tank provides a buffer as it gives the compressor time to react by increasing the engine speed and producing air before the tool stalls. It also has the advantage of lowering the duty cycle of the compressor system.
Pressure Gauge
While not critical to system performance, a pressure gauge is important for fine tuning the system and simplifies any potential troubleshooting. Install a 200 psi pressure gauge downstream of the air discharge valve.
Pressure Regulator and/or Lubricator or FRL
The compressor can produce air pressures up to approximately 175 psi (1207 kPa). It is the responsibility of the user to know the pressure and air flow requirements of the tools powered by the air compressor system. An appropriate air pressure regulator and lubricator can be installed downstream of the air discharge valve. Failure to regulate the air pressure may cause damage to the tool.

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Air Receiver Tank
If an air receiver tank will be used with this system, a check valve (not supplied) must be installed to prevent damage to the system.
Once a check valve is installed, pressure in the air receiver tank will not be relieved when the compressor system blows down. This is normal operation.
Prior to performing any service work on the system, discharge any stored air in the air receiver tank.
If an air receiver tank will be used with this system, the following installation procedure must be used to prevent damage to the system.
The VMAC compressor system will automatically depressurize when it is shutdown, therefore the hose from the VMAC AOST to the air receiver tank must have a check valve installed; this prevents blow back and moisture from the receiver tank entering the AOST
While the air receiver tank can be installed at any height in relation to the AOST, the discharge hose running from the AOST must be installed as high as possible on the air receiver tank to prevent problems with condensation that may have accumulated in the receiver tank (Figure 62).
Drain the condensed water from the receiver tank daily.
Install the line to the receiver tank as high as possible

Check valve

Air Receiver Tank

AOST

Figure 62 — Air receiver tank

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Testing the Installation
Safety Test
Ensure the following has been completed:
Place the automatic transmission in “PARK” and apply the park brake. Turn the ignition “ON” but do not start the engine.
Note: Vehicles with push button start must be placed into “Service Mode” for the following tests (see the vehicle’s owner’s manual for instructions).
Check the control box to see if it is illuminated. If there is no display, there is no
power to the control box.
Press the “ON” button on the control box. The green LED should come on and
the compressor clutch will engage, this should be audible.
On systems equipped with VMAC’s digital throttle control, the “PRK BRAKE” LED will remain illuminated at all times, regardless of park brake position.
Prior to proceeding, ensure the green LED on the control box is still illuminated from the previous step. If not, ensure the vehicle transmission is in “PARK”, the park brake is applied, and the vehicle ignition is turned to “ON”. Cycle the compressor off, then on again to reset the safety parameters.
Release the park brake.
The green light on the control box should flash and the display will flash
“PARK BRAKE”.
Apply the park brake again and press the “ON” button. The green light
should come on. With the brake pedal firmly depressed, shift the vehicle into “REVERSE”.
The “STATUS” and “PRNDL” LED’s on the digital throttle control will turn off. The green LED on the control box will remain illuminated. Shift the vehicle back into “PARK”. Cycle the compressor off, then on again to reset the safety parameters. Repeat these steps in all gear selector positions to ensure the “STATUS”
and “PRNDL” LED’s on the digital throttle control will turn off (Note that on some vehicles, the engine speed will remain elevated, and the “STATUS” and “PRNDL” LED’s may remain illuminated when the vehicle is placed in “NEUTRAL”, this is normal).
Press the “OFF” button on the control box. Turn the ignition “OFF”.*
Note: Vehicles with push button start must be taken out of “Service Mode” for the remainder of the tests (see the vehicle’s owner’s manual for instructions).

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Place the vehicle in a safe operating position and adequately block the wheels. Ensure that there are no people around the vehicle prior to performing the following tests.
Before Starting the Engine Checklist
Ensure the following has been completed:
Verify that the compressor oil level at the AOST sight glass is correct. Verify that the vehicle coolant level is correct. Perform a final inspection of the installation to ensure everything has been
completed.
Check all wiring for security and protection. Ensure nothing is touching the
compressor body.
Install the VMAC Air Test Tool (P/N: A700052) with the 70 cfm (0.190 in) orifice
installed and the ball valve closed.
Ensure all of the compressor outlets are closed. Ensure the parking brake is engaged and the transmission is in “PARK”. Start the engine.
After Starting the Engine Checklist
Check for any leaks, confirm belt alignment, and ensure the belts are rotating
properly.
Close and latch the hood. Allow the vehicle to reach operating temperature. Turn on the compressor.
The VMAC digital throttle is a “slow ramp” throttle. Each time the system is powered on, it will quickly increase engine speed to 1,500 rpm; then increase to maximum VMAC rpm over 8 seconds (provided the system has not reached full system pressure before maximum VMAC rpm is reached).
After the initial slow ramp, the throttle will respond normally to air demand
When the VMAC system is first engaged, the engine speed should increase to
1,500 rpm and then drop down to VMAC base idle (approximately 1,000 rpm) once system pressure is reached.
With the system running, check for:
Coolant leaks. *Compressor oil leaks. Allow the compressor to run until the system reaches full system pressure. Engine speed should reduce to between 900 rpm to 1,000 rpm. Turn off the compressor. Shut down the engine. Drain any stored air is drained from the system.

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Check the compressor oil level after the engine has been shut down and the oil
level has had time to stabilize.
Ensure any stored air is drained from the system prior to adding oil.
Add oil as necessary to bring the level to the “MAX” line in the sight glass and
check for leaks.
Start the engine. Turn on the compressor and allow it to build to full system pressure. Release the park brake.
· The control box should read “PARK BRAKE”, the compressor clutch should
disengage and engine speed should reduce to OEM idle.
Re-engage the park brake and start the compressor. Allow the engine speed to stabilize after re-engaging the compressor.
With the brake pedal firmly depressed, shift the truck into “REVERSE”.
The engine speed reduces to OEM base idle (Approximately 650 rpm). The green LED on the control box remains illuminated. The “STATUS” and “PRNDL” LED’s on the digital throttle control will turn off
and engine speed will reduce to base idle.
Shift the vehicle back into “PARK”. *Cycle the compressor off, then on again to reset the safety parameters. Repeat these steps in all gear selector positions to ensure the engine speed
does not increase unless the gear selector is in “PARK”.
Digital Throttle Auto Calibration
When first installed, the VMAC digital throttle will perform an autocalibration as it adjusts to the vehicle’s tune, this process takes approximately 3 minutes.
Remove the orifice from the VMAC Air Test Tool. Open the ball valve slowly, until the system maintains approximately 85 psi. Allow the system to run for 3 minutes while the VMAC digital throttle calibrates
itself. During this time, engine speed may gradually increase until achieving the maximum VMAC rpm (2,600 rpm).
Close the ball valve. Allow the compressor to run until the system reaches full system pressure. Confirm all air valves are closed and the system has no air leaks. Turn off the compressor. Ensure any stored air is drained from the system.

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Final Testing
Ensure the following has been completed:
Operate the system with an air tool (or the VMAC Air Test Tool with the
appropriate orifice installed) for at least 1/2 hour (1 hour preferred).
Road test the vehicle for approximately 14 miles (20 km). Observe the compressor operation to ensure that the belt alignment is good
and nothing is rubbing or contacting hot components.
Check all components, connections and fasteners once the engine is turned off
and the system has cooled.
Check the coolant level after the engine has been operated. Check the compressor oil level after the engine has been shut down and the oil
level has had time to stabilize.

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Performance Testing and System Adjustments

Performance Testing and System Adjustment
System operation can be tested using the tools that will be operated by the system or by using the VMAC Test Tool (A700052) with the 70 cfm (0.190 in) orifice in the outlet to simulate tool use (Figure 63).

JIC Adapters

Orifice

Ball valve

Install orifice here
Figure 63 — A700052 VMAC Air Test Tool
Disconnect all downstream equipment (hose reels, etc.) and connect the test tool directly to the discharge fitting on the AOST.
Ensure there are no leaks in the test tool. The system may not idle down if there are leaks in the lines or fittings.
Install the VMAC test tool at the AOST outlet with the 70 cfm (0.190 in) orifice. Ensure that the ball valve is closed. Place the transmission in “PARK” and fully apply the park brake. Allow the engine to run until it is at operating temperature. Turn on the air compressor system and allow it to operate until the oil is warm. Observe the pressure gauge. Pressure should be approximately 150 psi.
Open the ball valve on the test tool and observe the engine tachometer:
Engine speed should increase to approximately 2,600 rpm. Close the air valve slowly to allow the system pressure to rise. Once system pressure is at maximum, slowly open the ball valve on the test tool
until the pressure on the gauge begins to drop. Engine speed should ramp when the pressure drops to approximately 140 psi.

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Digital Throttle Control Operation and Adjustments
The VMAC digital throttle is a “slow ramp” throttle. Each time the system is powered on, it will quickly increase engine speed to 1,500 rpm; then increase to maximum VMAC rpm over 8 seconds (provided the system has not reached full system pressure before maximum VMAC rpm is reached).
After the initial slow ramp, the throttle will respond normally to air demand.
The throttle control is configured at the factory for optimum performance at maximum cfm. In applications where maximum cfm is not required, or noise is a concern, the throttle control can be adjusted to reduce the maximum VMAC rpm.
Safety features
The throttle control has built in safety features that will disable the system if an unsafe condition is detected, or either of the lock out parameters is not met (the vehicle must be in “PARK” and the park brake must be engaged).
If an unsafe condition is detected, the “STATUS” LED will turn off, and engine speed will return to idle. Once all unsafe conditions have been removed, the system must be cycled off, then on again to reset it. Once the system powers up, the “STATUS” LED will illuminate, and the system will operate normally.

Figure 64 — Throttle control
If the park brake is released, or the vehicle is placed in gear, the “STATUS” LED and the corresponding lockout LED will turn off and the throttle control will deactivate. This will reduce engine speed to base idle.
In order to activate the system again, re-engage the appropriate lockout and cycle the VMAC “OFF” then “ON” via the control box.

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MAX RPM
Maximum VMAC rpm can be adjusted between 1,500 rpm and 2,700 rpm (in 50 rpm increments) via the “” or “” buttons in the “MAX RPM” column.
If the system is at full system pressure while the rpm is being adjusted, the engine speed will increase to the new value for 4 seconds, then return to base idle.
RAMP UP PRESSURE
“RAMP UP PRESSURE” is the amount of pressure the system will drop before the engine speed is increased to generate air; as air continues to be used and the pressure drops, engine speed will increase until maximum VMAC rpm is achieved.
“RAMP UP PRESSURE” is set to 140 psi (10 psi below the factory default maximum system pressure of 150 psi). This allows for a small amount of air use without the need to increase engine speed.
“RAMP UP PRESSURE” should only be adjusted if the maximum system pressure is changed (via the inlet regulator). To maintain proper performance, and rapid response to air demand, ensure the “RAMP UP PRESSURE” is set at no more than 20 psi below the maximum system pressure.
The “RAMP UP PRESSURE” can be set to “100 PSI”, “120 PSI”, “140 PSI”, or “160 PSI via the “” or “” buttons in the “RAMP UP PRESSURE” column; an LED will illuminate beside the setting that has been selected.
Factory Reset
The throttle control can be reset to factory default values via a button inside the throttle control box.
To perform a factory reset, turn the system on and allow the engine speed to drop to VMAC base idle (approximately 1,000 rpm). Using a paper clip (or similar object), push and hold the factory reset button for 5 seconds. All of the LED lights will illuminate for several seconds while the settings revert to their defaults. Once the LED’s return to their normal state, the system is ready for use again.
For more information on the digital throttle, including error codes, see the related article the VMAC Knowledge Base: https://kb.vmacair.com/help/vmac- digital-throttle-control

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Accessory Products from VMAC
Compressor Service Kits
200 Hour or 6 Month Service Kit Part number: A700019 Includes 5 L VMAC high performance compressor oil, oil filter, air filter, and next service due decal.
400 Hour or 1-Year Service Kit Part number: A700020 Includes 5 L VMAC high performance compressor oil, oil filter, air filter, coalescing filter, pressure relief valve, muffler, and next service due decal.
Air Aftercooler — 70 cfm
Part number: A800070 Improves tool performance and extends the life of air tools; removes up to 80% of water from compressed air; includes automatic water drain.
· Max air flow: 70 cfm / 175 psi. · Port size: 3/4 in NPT inlet and outlet. · Electrical: 12 V. · Dimensions: 17 in (43.2 cm) L × 8.0 in (20.3 cm)
W. × 14.5 in (36.8 cm) H.
· Weight: 35 lb (15.8 kg).
Filter Regulator Lubricator (FRL) — 70 cfm
Part number: A700151 Extends the life of air tools; filter removes contaminants from the compressed air, adjustable regulator can reduce air pressure going to tools, lubricator adds atomized tool oil to the air stream to lubricate air tools (Tool oil not included).
· Max air flow: up to 70 cfm / 150 psi · Port size: 3/4 in NPT inlet and outlet
1/2 in × 50 ft Hose Reel
Part number: A700007 Spring-loaded 1/2 in × 50 ft hose reel; steel construction; full flow shaft and swivel for maximum performance.

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VMAC De-icer Kit
Part number: A700031 Cold climate heater package for operating VMAC compressors in cold climates; proven at temperatures of -30 °C (-22 °F). Requires 12V DC at 10A.
10 Gallon Air Receiver Tank w/ Mounting Feet
Part number: A300047 Air receiver tanks are used for lowering compressor duty cycle and removing water from compressed air. Recommended for optimum operation of VMAC Hydraulic Air Compressors, VMAC Diesel Driven Air Compressors, UNDERHOOD40, UNDERHOOD70 Green Series Air Compressors, and VMAC Multifunction Power Systems, which include standby mode; ASME certified; includes fittings, 200 psi pressure relief valve, tank drain, and 200 psi pressure gauge.
· Max pressure: up to 200 psi. · Dimensions: 30 in (76.2 cm) L × 10 in (25.4 cm) D. · Weight: 33 lb (15 kg).
35 Gallon Air Receiver Wing Tank
Part number: A300010 Air receiver tanks are used for lowering compressor duty cycle and removing water from compressed air. Recommended for optimum operation of VMAC Diesel Air Compressors, Hydraulic Air Compressors, UNDERHOOD40, UNDERHOOD70 Green Series Air Compressors, and VMAC Multifunction Power Systems, which include standby mode; ASME certified; includes fittings, 200 psi pressure relief value, tank drain, and 200 psi pressure gauge.
· Max pressure: up to 200 psi. · Dimensions: 73 3/4 in (187.3 cm) L × 14 in (35.6 cm) D. · Weight: 95 lb (43.1 kg).

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Notes

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Warranty Registration

This form must be fully completed and returned to VMAC at the time the vehicle is put into service. Warranty may be void if this form is not received by VMAC within 3 months of receiving the vehicle, or 200 hours of operation, whichever occurs first.
VMAC’s Warranty policy and registration can be viewed online at: www.vmacair.com/warranty

Product Information
System Identification Number: V Compressor Serial Number: P

Owner / End User Information

Company Name:

City:

State / Province:

Phone: ( )

Email Address:

Date vehicle was put into service:

/ /

Day

Month Year

Installer Information
Installer Company Name: City: