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Discussion Starter #1 (Edited)
Anyone have a thred for info, how to get more oil to the cam? The engine is coming out for a freshen up. It's eaten (3) cams to date first one was stock, next two mild RV, lasted less than 10,000 miles. What the @#%^& ?????? :shaking: I did not install either cam. This engine has 89,000 miles.:confused: My `94 2500 Suburban was awesom, it never needed work. I traded it off with 239,689 miles on it's 454, running strong. It must have been built on a Wed.:D
 

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is it the same lobes each time?

are you high rmp-ing the motor? 6000+

the fact that it isnt right away that is weird.

i wonder if its over tightend rockers?
to strong of a spring?
warped block?
plugged/plugging passages?
 

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I here that all new oil has what ever additive you need for a non roller cam was removed

someone told me to only run rotella T in older engines with regular lifters

I don't know this for fact it is just what i have herd :question:
 

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Use GOOD lifters. The ones with obviously hardened bottoms. And the high-zinc Rotella oil in non-O2 sensor engines.
The fact that your cams last longer than a day but less than 100,000 miles means crappy foreign lifters bought by the pallet hampered by no-zinc modern oil.
 

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is it the lobes, or the bearing surface? if it's the bearing surface, you have to be VERY careful as to proper bearing grooving, and the "o'clock" position of the oiling hole in the cam bearing, this varies between big blocks, they are not all the same. If it's lobes, and the same ones, then I would check to be sure that A. the valve guide is smooth with proper clearances, B. the valve itself is straight, and C. the valve spring pressure on those. If it's random ones, then cheap lifters, or a bad install. They aren't using old lifters with a new cam, etc. are they? Also, there are two threaded hex plugs that go right behind the timing chain. Some people (me included) drill them with a VERY small hole to help chain lubrication. However, if some no-mind drilled a big hole in them, this could be a source of low upper deck oil pressure.
 

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I used to build and run bigblocks in everything, I have seen the same problem before . When you pull the cam out ,check the surface behind the top timing gear. It is a common place for wear in a bigblock and if the cam is walking back the lifters wont spin on the cam right . If the block is worn it will need repaired they make a bearing kit for it but requires machining.There are a few timing gear sets that have the bearing that dont require machining but depends on how bad the block is trashed.If that looks ok have the valve springs checked for bind or being way to (strong which I have never seen). Make sure the cam bearings are not trashed and if all that is good make sure you use a lot of cam lube for breakin and fire the motor and run at at least 2000 to 2500 rpm for 20 minutes as soon as it fires .I know it can be a bitch trying to put anti freeze set timing and such when it first starts but it is verry important to break the cam in.
 

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I had the same problem in a mid 70s engine also. Finally got pissed off enough and pulled the entire engine out and pulled it completely apart. Turns out some of the lifter bores were too tight, and not allowing the lifters to spin correctly. The machine shop honed them out, installed new cam bearings--never had a problem after that.
 

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Also, problems affecting big block cam oiling can be solved by machining a groove in the distributor and installing an o-ring in the groove which lets less oil by and keeps it going to the cam.
 
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