VMAC Underhood Throttle Control Adjustment

Technical Support Subject VMAC Underhood Throttle Control Adjustment Document Version Department Revision Details Revised by Tech Engineering Implemented EXT-VR-015 A Tech Document Release SP 9 Nov 2015 JP 9 Nov 2015 N/A 9 Nov 2015 Page 1 of 2 Knowledge Base: www.kb.vmacair.com Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 System or Parts affected  VR 70  VR 150 Index System or Parts affected.............................................................1 Before you start............................................................................1 How to Adjust VR Throttle Max RPM setting ............................1 How to adjust the idle down screw (IDP)..................................2 Demonstration...........................................................................2 Before you start Place the truck in a safe operating position and block the wheels. Ensure that there are no people around the truck before beginning the test.  Install the VMAC Test Tool directly into the Air Oil Separator Tank.  Make sure that the ball valve is closed.  Place the manual transmission in neutral or the automatic transmission in park and fully apply the park brake.  Allow the engine to run until it is at operating temperature.  Operate the air compressor system until the oil is warm. Trouble shooting sections: How to Adjust VR Throttle Max RPM setting Note: When making adjustments to the throttle control module screws, count the turns as there are no stops for the adjustment screws, they will turn indefinitely.  Observe the pressure gauge. Pressure should be approximately 150 psi and should idle down to VMAC Base Idle (Diesel engine: 1000 RPM approx. / Gas engine: 1100-1200 RPM approx.).  Open ball valve on flow test tool A700152 (or similar) with orifice removed, to bleed off air and maintain 80-90 psi. 6. Leave the ball valve open on the test tool to maintain 80-90 psi.  With the ball valve open, turn the max rpm screw until VR throttle is Diesel engine: 2100 RPM approx. / Gas engine: 2400 RPM approx. This will provide approx. 58CFM @ 95 – 105 PSI with VMAC Test Tool and correct Orifice in place). (See Figure 1)  Max RPM is now set Figure 1 Technical Support Subject VMAC Underhood Throttle Control Adjustment Document Version Department Revision Details Revised by Tech Engineering Implemented EXT-VR-015 A Tech Document Release SP 9 Nov 2015 JP 9 Nov 2015 N/A 9 Nov 2015 Page 2 of 2 Knowledge Base: www.kb.vmacair.com Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 How to adjust the idle down screw (IDP) *This must be done after max rpm is set  Turn system on and pressurize to 150 psi.  Slowly open the ball valve to allow pressure to bleed off 10-15 psi (maintain pressure on gauge at 135-140 psi). At this point the RPM’s should increase approx. 100 RPM.  If RPM’s do not increase, leave the ball valve open on the test tool to maintain pressure on gauge at 135-140 psi and adjust Idle Down Pressure screw clockwise until the RPM increases approx. 100 RPM.  After you have completed adjustments, re-test. Turn off compressor system, turn off truck and redo testing.  Open ball valve wide open so rpm increases to max (Diesel engine: 2100 RPM approx. / Gas engine: 2400 RPM approx.). Then close ball valve and let pressure build to 150 psi.  Open the ball valve to allow pressure to bleed off 10-15 psi so pressure on gauge is 135-140 psi. At this point the rpms should just increase to (Diesel engine: 1000 RPM approx. / Gas engine: 1100-1200 RPM approx.).  Throttle is now set up. Demonstration A video of this procedure can be found here: http://youtu.be/xu2GCPoSy78