Cm570 engine brake vibration and weak jakes

[Rawze]

The overhead valve adjustment does not set/adjust the strength of the engine brakes. The valve adjustment is either correct .. or incorrect and that is all to be done.

Inspect the overhead cams for flaking etc. and ensure no lobes are damaged or worn down.

It also looks to me anyways, like all the rockers are functioning/operating just fine.. though I don't make it a habit to play with them like that. Activating the jake solenoid that only controls one single cylinder IS going to be very different than the solenoids that operate 2+ cylinders at a time.

When they are fired by the ecm instead of by hand, do they activate properly?.

What someone needs to do as equally important, is an injector leak test, to make sure no injectors are leaking fuel into the cylinders during jake operation.

Here is how it is done:
http://rawze.com/forums/showthread.php?t...8#pid67948

I am no expert on digging into CM570 engine brakes specifically, however, I do know that an old 570 with a non-VG turbo is going to have a significantly weaker engine brake overall, than anything more modern... especially at lower rpm ranges. If that turbo is weak, mis-matched to the engine, or has damaged turbine then the engine brake will be effected by that as well.

Just my own thoughts on it any ways.