Macktech689

sorry to say I already have one, I keep it in my toolbox right next to my magic wand and x-ray glasses.

Check all the return fuel lines from the heads to the injection pump, they look like small plastic air lines. any leaks cause loss of prime. Also check the jumper between the heads by the valve covers

North Carolina

Should have also mentioned to make sure all the oil collected in the bolt holes is removed and to make sure the rocker shaft is pulled down tight against the cam blocks before torqing the bolts

Yes Kyle the trim code for each injector needs to be programmed in the ECM, also a learned data reset should be done. Injector torque procedure is 15 FT pounds + 180 degrees then loosen to 7 to 11 FT pounds retorque to 15 +90 degrees. MP7 rocker bolts 44 FT pounds + 100 degrees. MP8 rocker bolts the 12 small bolts are 18 FT pounds +120 degrees, the big bolt is 44 ft pounds + 120 degrees. Hope this helps RM.

I am a service tech at a Mack dealership in the Southeast US, Hopefully I can help some of you guys out from time to time. Have been repairing Macks since 1987.

VMAC 1 has 2 modules, the VECU monitors vehicle functions and the FIC controls fuel injection. Both " should" both disconnected before any welding operations, but removing the battery grounds is usually sufficient. Keep in mind control modules and programming for older trucks is very expensive.