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Discussion Starter #1
I’d appreciate some feedback to help me decide wether or not I’m tearing the tranny out of this thing this week.
 

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Discussion Starter #3
#7 cam bushing. Oe motor has 15k on it. I have never torn down a used Cummins so I have nothing to compare it to.
 

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Discussion Starter #4
I mentioned Tranny cause it’s 2020 & trendy. It’s gotta come out to replace the bushing.
 

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Need to measure to thousands of inch , picture is not going to tell you.
What does cam measure, what do bushings measure?
Other things I would be worried about
What was oil pressure?
What does valve train look like?
All that rtv/sealant on plug ends up in oil should remove clean install properly.

Specs for cam and other important info are in FSM in newbies guide here
https://www.cumminsforum.com/forum/22069665-post1.html
 

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Discussion Starter #6
I’ll rephrase & elaborate: for guys that have torn down used or high mile motors how does this bushing compare to ones you’ve physically seen? At what mileage would you say an average bushing/bearing under normal conditions has its copper/tin worn off down to the base alloy in a Cummins.
 

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Offhand, either the bearing install was pooched or you got a bad cam. Just depends on how well the engine was cared for and how it was used but normally the cam bushings look quite good in the 200-300k range.
 

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Discussion Starter #8
Thanks. That’s what I needed....When I got the truck back from the shop the fuel pump relay wasn’t installed so I know they primed the whole system with only the cp3. Probably cranking on it for minutes with no oil pressure & probably wiping the assembly lube off the cam.
 

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Oil wet crank or cam bearings are not going to be damaged by long cranking over for bleeding the fuel system. Plus it starts pumping oil while cranking.
 

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Thanks. That’s what I needed....When I got the truck back from the shop the fuel pump relay wasn’t installed so I know they primed the whole system with only the cp3. Probably cranking on it for minutes with no oil pressure & probably wiping the assembly lube off the cam.

No or Low oil psi should show wear in other components that are further down oil supply feed ie, look at other upper valve train components they get oil last.
 

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Discussion Starter #12
Great, thanks. Who’s Eric? The cam was installed in the new engine before it was installed in the truck, the fuel system was completely drained as the external filter was replaced as well as the stock filter housing being emptied & cleaned out. I was surprised how much debris was in the bottom. So I’m assuming even if the external filter & the factory filter housing were filled prior to cranking it’d take some time to prime the fuel system & to get good oil pressure throughout the system. Within the first 100 miles of break-in the rockers were so far out of adjustment the black plastic retainers broke on 5 of them. I’m also assuming the rockers were out due to the cam bushings wearing down. I replaced all the rockers/pedestals with the new 6.7 versions, installed Hamilton hd pushrods & 103 springs. I was pissed that all that brand new stock stuff took such a beating. S**t went south real quick when they declined to do anything to right the problems.
 
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