Retiming the CP3 To TDC
 

I read somewhere that this person had a slight engine knock. He retimed the CP3 to engine tdc, and POOF, no more engine knock. The CP3 is nowhere near like a P-Pump, VP44, or a VE pump, where they have 6 individual injector lines, compared to a single high pressure fuel line like a CP3 has.

Is it a joke, or has someone here actually do it, and end up with the same results??

I have only taken one off before. but the Cummins Manual never said anything to TDC the engine or the pump. plug and play basis so it ran great when i was done.

Mine was fine after I installed it as well. No timing or anything needed to be done.

BS

it is BS I agree but. I was looking around in the book and it says that no timing of pump or engine is needed. but i was thinking about it.
It is a rotary pump. So what could be doing is preloading the pump. or taking the play out of it. so it wont knock. But if its knocking I am thinking the pump is worn and not applying full pressure enough to run great but not to its max performance.
so really think about it Your not re timing it to the engine like you would a VP 44 or others your just taking the preload out of the pump. not really timing it
So if its knocking it may be time to just buy a pump. this may work for a little while but its going to happen again when the play is out of the pump again

The pump generates the pressure, the injectors fire it. There's no timing in this pump style. There's no change in where the gear is placed. Again, All the pump does is create pressure, no plunger or DV setup per injector so it couldnt make any change in the performance of the truck.

Thats how they get away with running a second cp3 off a belt. No Need for accurate timing.

Interesting. I will remember that. But I agree. I bet he just temporarily fixed the problem, or maybe just the noise...?

Its not timing as we know it, but more of a phasing the CP-3 to TDC. Yes, it is a valid operation and yes it will redure the knock if thats the problem, no BS.

The CP-3 is driven at half the speed of the crank with one of the 3 high pressure cylinders hitting TDC at the same time one of the cylinders does. If they do not correspomd fairly close the slack in the gear drive will create a knock.

The absolute postive way would be to time the engine off the damper and the IP of the gear and match as close as possible with a dial indicator. Since thats tough, the easier way to do it is mark your damper pulley for about 20 degree increments somewhere you can track. Pop the gear off the CP-3, rotate the 20 degrees, retighten the gear, check for noise again. If you don't get a reduction in 3 tries its not a problem.

Yes, I have done it and Yes it made a difference.

yes its just to fix the noise. we all know how to advance the timing on our CR engines and this is not what they are trying to accomplish. If you have a knock you can try this. to get rid of the cp3 knock. But its seems like it has a timestamp on it. It may work for a mile or a while. once it get play in the pump again it could be GONE when your broke on the road or in the Ghetto's of Chicago your SOL