Thread: What would cause this lifter failure (pics attached)

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I started tearing down my SBC 350 to change out the cam, and I found 2 lifters with (I think significant) damage. They were on the front driver cylinder exhaust, and rear driver cylinder intake.

I have had problems with this bank before with roller tip rockers. What happened before is that the rockers had become very loose to the valve stem tip, slightly deforming them (yes these 2 cylinders). I switched to full roller rockers to replace the damaged rockers, thinking that they were simply way out of adjustment. What I am thinking now is that the lifters were collapsed or not pumping up, which caused the looseness originally. What I am worried about is if the oil FEED in this area is blocked, which is why the lifters did not pump up. HOWEVER when I used a tool in the dist hole after I put the rollers in, I DID get oil at EVERY rocker. Many I'm a bit confused and frustrated.

Both lifters are pretty badly cupped, and chewed up on the outer edge. The worse of the 2 had a discolored roller rocker. I suspect the color change was from excessive heat. I did not notice anything at all unusual (else) about the rockers, pushrods, valve stem tips, or anything else I could see.

I have my thoughts, but I would like to know if anyone has seen this type of failure and what causes it? Also is the discolored lifter related? If the cam and lifters are toast (likely), are there other potentially damaged parts?

Thanks in advance.

The cam and lifters are toast. Review your break-in procedure, did the engine fire up immediately and go to 1500-2000 RPM and stay there for some time? If not the cam and lifters were damaged immediately. What spring pressure are you running? What brand of lifters? Cam? Lots of cam lube?
I think you have it backwards, the rockers didn't cause the lifter failure, the cam went first, causing slack and pounding the rockers out.
All that metal went into the oil sump and through the engine. Flush the system and change the oil and filter twice after the cam change. Best would be disassembly and inspection.

I am not a cam expert but those lifters are TOAST and I'm sure the cam is also. Not being there to see it I bet the lifters were set to tight. Other damage??? All the missing material is floating around in your engine . You may want to tear it down but thats your call.

My guess is you have some weak valve spring which caused the lifters to bounce, along with the valves but the lifters got the short end of it all..

I partially took apart the lifters at my desk. They are 2 piston style. The first piston came out easily, but it looks as if there is galling on the inside walls (which would have prevented the lifter from properly compressing. I'll take them the rest of the way apart at lunch and see what I find. The engine was running before all of this happened. I took the engine out of my friends Jeep and then into mine. At that time, I looked at all the lifters and they looked good. Then soon after, the rocker became loose and rattly. I think I got a few of them dirty, quickly causing the intial failure of the rockers and likely cam damage (no question there). I'll be taking the cam out tonight or tomorrow night.

I have been regularly changing the oil, and will again with this cam change. I WILL degree the cam and break it in proper with Shell Rotella. I wonder if I could have burnt a few valves if the lifters were acting solid and I tightened 1/2 turn past?? I really don't wanna take the head off.

I have a new cam and lifter set (lunati) on my table. The spring force is 132lbs (see picture of the specs).

Denny, is there a way to check cam bearing clearances without doing a teardown (with just access from the front, with heads on, and pan on)?

Do you think my explanation is plausible (the lifters froze, becoming mostly solid, then I tightened 1/2 past no movment). If I had less oil in just those lifter pockets, why did oil come out when I turned the oil pump with a tool in my drill? Also, why would I not see much more wear on the rocker trunions and pushrods? Not at ALL saying your wrong, just trying to rationalize and consider the merits of each possibility.


I'm interested to see the cam when I take it out.

I also had this happen to me 2 times before getting it right.I also remember reading in a Hot Rod magazine that this was comon.Something about companies useing cheap material for lifters ,and oil not having the properties "it used to".It advised on useing a different type oil for break in.Maybe some one can inform you better on this.Also about the rockers did you shut the engine off as soon as you heard it ticking or did you floor it and try to get the ticking to stopThe lifters did have some friction on them ,you can tell by the discoloration.

Also when you pull the cam it will look worse then the lifters.

You need to pull the motor,no amount of flushing etc. is gonna get the metal out of it, metal is gonna be imbedded into the bearings and cause a very short life.......... I would also look very close at the oil feeds for those lifters as I have seen the holes in the lifter bores clog with debris.

Originally Posted by HWORRELL

You need to pull the motor,no amount of flushing etc. is gonna get the metal out of it, metal is gonna be imbedded into the bearings and cause a very short life.......... I would also look very close at the oil feeds for those lifters as I have seen the holes in the lifter bores clog with debris.

I absolutely agree.

I pulled the cam last night, and the journals were a bit rounded (those 2), but not as bad as I expected. Although it is pretty hard to tell if the shape has changed.

If I were to pull the engine, I would have to disassemble completely to do a flush, right?

I would also have to send it to a shop (at least the best way would be to do that) to have it flushed and cleaned? (Hot tanked, etc).

Originally Posted by pnut

I pulled the cam last night, and the journals were a bit rounded (those 2), but not as bad as I expected. Although it is pretty hard to tell if the shape has changed.

If I were to pull the engine, I would have to disassemble completely to do a flush, right?

I would also have to send it to a shop (at least the best way would be to do that) to have it flushed and cleaned? (Hot tanked, etc).

Man it's a lot of work & expense but it's the only way to do it, dissassemble,hot tank, new rings and bearings. buy an engine cleaning brush kit and clean everything with hot soapy water, those brushes and air, when you reassemble use cam lube on the cam & lifters...

Originally Posted by DennyW

From reading your discription, I would say to check your clearances on the cam bearings. If the clearance is tighter on 1 or 2, and the rest are looser, guess what ? The tight ones will starve on oil.

Also, never rule out the new parts. I have gotten a few that were bad right out of the box.

The hardness depth on stock Chevy cams in general are not very deep, and it doesn't take long to go through that if not properly done on the breakin.

Note: I was talking to a engine builder, and he told me that 2 cams from Lunati had went flat on him. He switched, and no more problem. I'm not knocking them at all, cause I know they have good products. Just a note on this is all.

Chipped lifters indicate chatter. Make sure you use a slick oil. Also, if the lifter holes are mis aligned in relation to the cam lobes, or the ramp on the cam is to steep.

Denny,I would guess the Lunati cam failure was due to the lifter crown and not the cam it's self.

Originally Posted by DennyW

Maybe, but that's not what Dave told me. We went to college together for automotive in the 70's, and he has been doing engines of all types for years. He said they were telling him he didn't break the cam in right. I know better than that myself. This guy is very fussy when he builds an engine. Clean room, and the whole nine yards. The third cam, he used another brand, same procedure, and no failure. That was in the same engine the other 2 cams were installed. That was his final test to see if it was the cam, or an engine problem. So the same engine was used. It is still racing the track.

ps, Bill, I'm not advertising this. Just showing that the guy that told me has lots of experience in this field. I took address and phone number off his card.

In our IMCA mod. engines we had a couple cam problems and after checking into a few area's we found brand new lifters from two different cam companies that had a small dish in the lifter face rather than a crown.

Originally Posted by DennyW

Yes, that happens also. That's one reason I mentioned that it could have been the lifters. Maybe the Monday, Friday thing, or the checking of clearances slipped by a few of them. Now, you never know where you may get your parts from. If you see sand, or taco sauce in the box, take them back.

I know what you are saying about the sand or taco sauce.
I had a brand new set of TRW pistons that I had bought about 12 to 15 years ago that had a little to much taco sauce on them.
I think that was when I switched to JE/SRP.

Guys, I've heard of those type of problems with Lunati cams and I seem to remember that Crane had the same type of problems a few years back.
The old Isky 30/30 cam I've got has been in three differeent sbc's and I've never had a problem with it. BTW, the last time I looked on Isky's site the cam listed for a little over $600.