Keeps chewing up retainers/thrust

Why are y'all tapping or pressing the gear onto the cam?

I had my first one pressed on. It threw a camshaft posistion sensor code when I fired it up. The cam gear was pressed flat onto the cam. I tapped it the rest of the way on. I should have pulled it and completely corrected the error. This last one I went to a buddies shop and borrowed his press. This one was was done with perfection this time. I was so mad at myself for not checking the work on the other cam swap it is not even funny. I hate do-overs.


It did make me feel a little better when Tim B. made the same mistake. Mistakes happen, it just sucks when it does.
 
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First time was pressed on and bolt on gear retainer used...

Replaced recent retainer/gear in the block.

Warmed the gear in a convection oven, slid it in to cam and tapped it with a brass drift to bottom it out on the cam.

Allowed it to cool tgen checked end play and buttoned it up.
 
were the bolts that hold the thrust plate still tight? I've seen them back out before when a thread locker is not used
 
Best thing to do is pull the cam and inspect to see if you can find the issue. Hope you haven't pulled the gear already.
 
No, the truck is still driving.

I'm going to call Zach tomorrow and pick his brain, if I need to yank the cam, then I might just get a new one.

I was just hoping that I can just regear/retainer it and be sure that the gear is seated, but again I hate to keep throwing money at a never ending problem.

Eventually all those shavings from the retainer will screw something up in a bad way!!!
 
No, the truck is still driving.

I'm going to call Zach tomorrow and pick his brain, if I need to yank the cam, then I might just get a new one.

I was just hoping that I can just regear/retainer it and be sure that the gear is seated, but again I hate to keep throwing money at a never ending problem.

Eventually all those shavings from the retainer will screw something up in a bad way!!!

That is what I did. Put a new one in.
 
I always heat the gear to 400F and it slides on the cam like butter in a hot skillet. No tapping required.
 
Tapping was just to be SURE the gear was seated.

Sounds like that still wasn't enough...

Got in the truck to go to work just a while ago after it sat all weekend...DAMN it's loud after its warm.

It's much worse this time compared to last time.
 
If the gear was installed with the cam in the motor then tapping it may be what's causing thrust bearing failure.
 
How so??

I thought that doing so would be useful to ensure proper seat on the cam nose...

Not a good idea??
 
There is nothing but that thrust bearing (retainer) to keep the cam from moving front or back. When you tap the gear all the energy is being absorbed by the retainer.
 
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Can't say ive changed a gear with it in the engine, how are you keeping the cam from pushing into the block when your tapping on it?

Running it with clearance could cause the wear from slaping back and forth.

^^ Beat me to it, in my experience in similar situations tapping it would result in more clearance as the assembly bangs into the retainer the weight of the cam wants to keep going away from the gear.
 
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There is nothing but that thrust bearing (retainer) to keep the cam from moving front or back. When you tap the gear all the energy is being absorbed by the retainer.

^^ Beat me to it, in my experience in similar situations tapping it would result in more clearance as the assembly bangs into the retainer the weight of the cam wants to keep going away from the gear.

Agreed
X3
 
Crap...ok.

So my desire to ensure full gear seat, could actually caused my issue.

Damn

Thanks guys
 
99% of the time that I hear an issue, people have done something other than just pull the cam out press the gear off, press the gear on the new cam, add pre-lube, install, change oil, reset lash and then run.

There are so many things that we are not covering by the he said, she said game here. The best thing is to pull it down, isolate any issues that may be there, remedy them and then go on. If it is put together right it has no choice but to work correctly.

I have never installed a cam gear in the truck. It really scares me for a few reasons. The thrust is not the only thing holding the cam one way or the other. On CR trucks the tappets are relatively close to the journals and the fuel pump eccentric. If you have wiped out the thrust a few different times, the tappets have most likely been riding on the cam journal and the fuel pump eccentric, grinding it all down. All of the metal shavings that come from the tappet and the journals can get in between the lobe and the tappet. Not only that, but the tappets can be side-loaded in the lifter bore which can cause more issues. All of this can be avoided by doing the install correctly the first time........one and done.

Please, pull the cam out, check the tappets, lobes, thrust, fuel pump eccentric, back of the cam bore (rear plate) and the gears for any wear. At this point any thing else is using a "jump to conclusions mat" to diagnose the issue.

If there is anything we can do for you, feel free to call us.

Zach
 
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With good Cummins cam gear remove/install tool (If you search , you can find my posted part number) you can easily remove and install the cam gear when the cam is still in engine.
 
Pulled the timing cover and there is well over .050 of end play...so the cam comes out tomorrow, ordering a cam from zach and ordering new tappets, gear, retainer etc...

Gotta ensure its pressed on PERFECTLY...cause I ain't doing this again.
 
Don't go and buy a gear. I think I have an extra gear and retainer out of an engine we just bought...... If you don't mind used and free.
 
I left a message for you this morning with Ryan..I'll try again tomorrow morning, then we can discuss options.

Thanks Zach
 
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