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

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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.

Does anyone remember when the oil companies started to take zinc out of their oil.
I wonder with a flat tappet cam how much this will effect things?

Denny,take a look at this web site.www.JoeGibbsRacingOil.com
Then click under Why use JGR oil?
If you scroll down father you will also see some info. from Exxon.

Denny, is it safe to assume that you're not a fan of Lucas oil additive?
Since I bought the '91 Dakota with 145 plus on the clock I've used that along with Castol high mileage 5W-30 oil. It's a 318 with TBI and at the present time I don't want to rebuild as the engine doesn't smoke and uses less than a quart between oil changes (300 miles). What would you recommend?

Originally Posted by DennyW

Really good info. If you notice though, after 1.5 hours or so, (100-150 laps), they do say drain and replace oil for extended protection. It sounds like good stuff, but I use this, Schaeffer for years, and have had really good results. You must understand that I don't do full out racing, but have done some serious street and early drag races. Most of my replies are related to guys that build things for fun, street race, and do not have money for the big buck engines. (That sure would be nice though).

When I have built engines on a regular bases, I would build them to exceed what ever the customer wanted. I pretty much blue printed all the motors I did, even the daily drivers.

I know things are changing, and sometimes I fall behind a little on the latest changes.

http://www.cincy-racing.com/schaeffer/news.htm

The XP1 oil is for engines that operate at 250 F,over 9,500 rpm's,and 500 miles.
In the last year we have tightend up all our oil clearance's and we run a mix of the XP1 and the XP3.
We use to take out the inner spring on our flat tappet engines now we just use the "break in oil " for all the flat tappet engines.
We simply bring the rpm's up to about 2,500 and vary them every 2 min. up and down about 500 rpm's we break the cam in for about 25 min. with this method.We have had zero failures in over 35 engines.
We have also upped are seat pressure another 10 lbs. on the last 8 engines.
Are we right? Are we lucky?I don't know but so far so good.