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Discussion Starter #1
i had comp cams 818 sbc lifter with comp 943 springs and .675in .645ex lift cam with 1.5 rockers. these lifter had dyno time and 8 street miles. it was idleing and broke at idle. the way it looks is the lifter broke in the middle of the shaft for the roller wheel. so i rebuilt engine and threw it up for a loss. the other day i was looking at those lifters and noticed a few more were missing the c clip to hold the roller wheel shaft in and the shaft was almost out. could this be what cuase the lifter that failed to go bad. i was told by comp i had 245lbs seat pressure and those lifter were designed to hold 230lbs(i call bs on that).just curious what could cuase the problem.
 

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Got any pics ?
 

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Discussion Starter #4
i dont have pics. but the brok lifter looks like you cut it right down the middle of the roller shaft, still a half moon shape on both ears to roller. just shaft and roller missing. theres also no coloratio so i do see where it could have gotten hot. im just thinking that the c clips came out or werent installed correctly.i looked at these lifters before they were installed and didnt see any c clips laying in box. but now there also 3 other lifter with the roller shaft almost out the side with 1 c clip missing
 

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This is why I don't buy Comp lifters. I wouldn't waste too much time trying to figure it out...they're just not that good of a lifter IMO.
How would Comp know your seat pressure?
 

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Ronald Reagans Ultra Ego.
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This is why I don't buy Comp lifters. I wouldn't waste too much time trying to figure it out...they're just not that good of a lifter IMO.
How would Comp know your seat pressure?
Thats BS, I've been using comp lifters for years with no issues.

Where they new? what Lash? Oiling Restricted? Please tell the whole build and story.
 

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Thats BS, I've been using comp lifters for years with no issues.

Where they new? what Lash? Oiling Restricted? Please tell the whole build and story.
I appreciate that you've had luck with them, but it's not BS, and I wouldn't have posted it if it was. Do some research and look at the faliure rate of Comp lifters vs a quality lifter like Crower, Morel, Isky, etc. I won't take that chance in my or my customer's engines for what little price difference there is, and I gladly offer the observation to others. We're all free to make our choices.
 

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i had comp cams 818 sbc lifter with comp 943 springs and .675in .645ex lift cam with 1.5 rockers. these lifter had dyno time and 8 street miles. it was idleing and broke at idle. the way it looks is the lifter broke in the middle of the shaft for the roller wheel. so i rebuilt engine and threw it up for a loss. the other day i was looking at those lifters and noticed a few more were missing the c clip to hold the roller wheel shaft in and the shaft was almost out. could this be what cuase the lifter that failed to go bad. i was told by comp i had 245lbs seat pressure and those lifter were designed to hold 230lbs(i call bs on that).just curious what could cuase the problem.
I am curious as to what your lifter bore clearance is/was. I have a new set of Comp Endurex solid rollers that I mic'ed the other day, and found them to be .841". Normal hydraulic Chevy lifters I have measure .8422", Isky EZX .842". I called Comp tech line the other day and they put me through to warranty. Warranty says "It's within our spec's" so tough luck! Pardon me? :-Yap .001" undersize on something that's only supposed to have a .0015"-.002" clearance IMO sucks. Is it possible that the extra clearance is causing the lifters to snap back and forth in the bores, as the wheel rides over the nose, causing some sort of strange harmonics. Could that spit out clips and break axles/bearings, or am I on crack?
 

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So the tolerance spread is is +/- .001? That's not going to work on a lifter clearance of .0015.
I never got a real answer as to just what their actual +/- "tolerances" are,......... might of been my tone of voice. The three blocks I have in the shop are all around .844". The Last Comp Lifters I ever bought would put me at .003" clearance in a brand new block. New Iskys on the way. Comps are on the shelf.
 

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Discussion Starter #12
the build is no oil restrictors and had 8 pulls on dyno. the motor sat for a year after build before cranking again. and sat another 6 months before it had drivetrain behind it. i would crank it for a few min at least once a week once it was installed in truck. once i got the drivetrains going and radiator we let it get up to heat and adj rockers to cam specs(also advised by engine builder) the engine has jesel shaf mount rockers and when we checked them was maybe a little on the tight side. needed .026in and .024 ex and was prob .002 tight on both. we reset them to .026,.024 and left it . drove it to friends shop(5 miles and thats when the lifter failed) at this point hasnt been reved over 3500rpm since dyno. i was looking at the roller wheels today and one of the lifters that the c clip was missing and shaft was almsot out the roller wheel was slighty scared. all the other were polished. im not shure if this is from the damage or from possible valve lash.

i also called comp again to today and this guy told me that the seat pressure wasnt a issue and was prob valve lash adj. but he said they would have to be way off and basically have alot of harmonics to nock the c clips out.ill try to post some pics tomorrow but it looks exactly like the pics posted in this thread.
 

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Discussion Starter #13
the engine builder is a comp dealer and said he had never seen anything like this before.he even mic ed the lifter bores and said they were normal. i check lifter size the other day and was .841 on my mic. since this engine failure ive used crowler lifters and have adj the same way from day one with no issues. i usally adj every 20 passes and almost never have a lifter off by more than .002-.004 with the jesel rockers. whats odd is this failure happend at idel. it made no noise and didnt do anything to let me know. and friend was standing there and said hey there oil gushing out. i check oild pressure and it was still good so shut off and found a ohole in oil pan. thats how we found it was damaged. very starnge. just curious becuase im gona try to fix the bad lifter and sale them. they have very little time on them but dont want to seel a faulyt lifter batch
Thats BS, I've been using comp lifters for years with no issues.

Where they new? what Lash? Oiling Restricted? Please tell the whole build and story.
 

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Thats BS, I've been using comp lifters for years with no issues.
They all have fail sooner or later, most of the time its not the lifter. The damage was more than likley on the Dyno from uncontrolled valve train. ( Good a guess as any)

When you have a company who sells more lifters than all the others put together you will always hear more stories, they are as valid as all stories told around the camp fire at Band Camp.

I have seen everyones lifters fail on Drag Week at one time or another.
 

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the build is no oil restrictors and had 8 pulls on dyno. the motor sat for a year after build before cranking again. and sat another 6 months before it had drivetrain behind it. i would crank it for a few min at least once a week once it was installed in truck. once i got the drivetrains going and radiator we let it get up to heat and adj rockers to cam specs(also advised by engine builder) the engine has jesel shaf mount rockers and when we checked them was maybe a little on the tight side. needed .026in and .024 ex and was prob .002 tight on both. we reset them to .026,.024 and left it . drove it to friends shop(5 miles and thats when the lifter failed) at this point hasnt been reved over 3500rpm since dyno. i was looking at the roller wheels today and one of the lifters that the c clip was missing and shaft was almsot out the roller wheel was slighty scared. all the other were polished. im not shure if this is from the damage or from possible valve lash.

i also called comp again to today and this guy told me that the seat pressure wasnt a issue and was prob valve lash adj. but he said they would have to be way off and basically have alot of harmonics to nock the c clips out.ill try to post some pics tomorrow but it looks exactly like the pics posted in this thread.
After getting the engine up to temp to lash the valves, did it look like the top end was getting plenty of oil when you pulled the valve covers? I know you said there are no oil restrictors in the block, but I think it's important to know if enough oil is/was getting to the top end.

What push rods are you using ... OD and ID ?
 

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Three comments-

Did you prime the oil system before initially running it on the dyno and after letting it sit for a few months or just fire it up with no oil in the system?

Same question as Jim above, did it look like the top end was getting oiled? What did the pushrod tips look like?

Also, once I had a cam that was nothing special but for whatever reason the base circle was ground where it set the lifters in some wierd place where it would not get oil to the top end. Strangest thing I've ever seen. Put a diferent cam in and it oiled fine. That was hand turning the engine and running a priming tool as well as with the engine running. Did an A-B-A test to be sure on it. Just another thing to check.
 

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Discussion Starter #17
right now im running cv products i think 7/16 pushrods. these are same pushrods when lifter failed. yes we did reprime motor since it sat for almost a year. engine always has over 85psi cold and 70 hot. as far as oil in valve covers i honestly dont remeber before the failure but i can tell you now there is always lots of oil in the heads.
 

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They all have fail sooner or later, most of the time its not the lifter. The damage was more than likley on the Dyno from uncontrolled valve train. ( Good a guess as any)

When you have a company who sells more lifters than all the others put together you will always hear more stories, they are as valid as all stories told around the camp fire at Band Camp.

I have seen everyones lifters fail on Drag Week at one time or another.
I agree 100%
 
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