CP3 Gear Install / Torque Spec?

[DAVe3283]

I am replacing the CP3 on my Suburban with an S&S SuperSport. It didn't come with the CP3 gear or adapter plate, so I pulled them off my stock CP3. Man, that gear was stuck on the stock pump! Had to use a puller and heat before it finally let go.

Given how seriously it was installed on the stock CP3, and the lack of a drive key, I am thinking it needs to be some sort of interference fit to keep from slipping on the shaft. But I can't find an install procedure for the life of me.

Does anyone have the process to install the drive gear on the CP3, including the torque spec? Or do I just wing it (heat drive gear in an oven, drop on cold CP3 shaft, torque to ~60 lb-ft)?

 

[PureHybrid]

I don't have anything duramax specific, but my Cummins book says nut with lock washer 105Nm +/-5. Shaft to be clean and dry, nothing about heating the gear. Backlash .075-.250mm.

 

[2004LB7]

I've installed a few and I don't remember having to make them very tight to lock the gear on the shaft. the taper is designed with the angle that will provide a very tight friction fit with not a lot of torque on the nut. as mentioned above, the surfaces need to be clean and oil free

and, if I'm not mistaken, the gear rotation is the same for tightening the nut so it can and usually does get tighter in use

 

[TheBac]

Looked back on DP at the torque specs (which should be here somewhere, too) -- 52 ft/lbs.

ON EDIT: Yep, I just looked at Henry's old torque spec post, and its 52 ft/lbs.

 

[DAVe3283]

Thanks guys! Sounds simple enough. Hoping to have the Suburban running again next weekend, just waiting on a couple more parts.

 

[TheBac]

Im just shocked its that low a value.

 

[Chevy1925]

its very much like the flywheel on a quad or motorcycle. it doesnt take a ton of torque to create a hell of a friction fit. you have to take the gear and plate off for dual pumps if you get a used pump. puller and a couple raps of the hammer on the back of the puller usually pops them for me. ive not needed heat yet.

 

[JoshH]

Make sure you use some sort of degreaser on the shaft and the gear where it seats on the shaft. If there is any oil on either, it can cause the gear to spin on the shaft.

 

[DAVe3283]

I figured a puller and a hammer would work. Started with a copper hammer, no dice. Then a standard ball-peen, still nothing. Finally got out a propane torch, and it let go. Sent the puller and itself nearly into the ceiling. Someone at GM was out to prove a point when they assembled that one LOL