_BANDIT_

Here is what happened to my engine after 3000 miles on it. Oil pressure is OK, no signs of running out of oil, no burning marks on the lobes.

Cam is CompsCams XE-274H, lifters were packed with the cam at the time of purchase.

Here are the pics for you to see:













How could this happen?

Apeiron

How did you break it in, and what oil did you use?

Greg Shorty

assuming the engine ran well and quietly (upon first start up) and there are no other valvetrain geometry problems, I would guess that the lifter in question failed to rotate freely in it's bore and began absorbing the increased friction/heat by sacrificing layers of metal.

Mic. the lifter bores and hone to a smooth surface, remove-inspect and clean everything that now has metal fragments on it, and reassemble. Been there, done it, felt stupid, still had to re-do it!

iroczracer07

iTrader: (2)

Apeiron and greg both have excellent points, so other than pointing out that oil companies have been removing minerals that were beneficial to reducing friction. Therefore, using just oil isn't going to cut it when breaking in a cam anymore.

Toehead

Buy some shell rotella T and use GM EOS, which should replace most of the missing ingredients, on your next break-in.

F-BIRD'88

See the scar on the lobe. That cam core was porous.
(Junk). You didn't have a chance with that cam. Should be replaced under warranty.
Even a minute flaw in the finished surface, or a small flaw just under the surface of the finished cam lobe will cause the cam to fail prematurly. GM had a bad run of 305 flat tappet cams just like that in the late 70's. Just about every 305 ended up with a 350 cam as a remedy.

5678TA

dont worry, that happened to me too.. and i run a solid flat tappet.. one lifter went down within 300 MILES!! it pretty much collapsed.. the cam wore a hole in the bottom of the lifter.. the previous cam i had before that one was a solid as well and my valve springs were solid roller units(my fault for not reading specs) and i wore down 7 lobes and lifters.. i got my recommended springs, and now i use Rotella T 15W-40.. and used GM EOS during break in.. i'm at over 600 miles with no problems.. same kind of cam..

Greg Shorty

I considered porousity originally, but when considering only 3000 miles and assuming it was not evident upon installation, I would be surprised to see any cam wear far enough to reveal it without some outside factor effecting it. I believe what you are seeing is the localized heat from extreme friction upon the contact patch 'sticking' the two surfaces together and causing them to tear apart. the softer alloy of the cam gives-way first and the material "pulls" out of the lobe and "wipes off" the lifter on the next revolution (along with a small portion of the lifter surface). If I remember correctly it's called pitting (or is it gauling?)

sofakingdom

iTrader: (1)

People bash on cams all the time these days; especially Comp. It's REALLY bad on some of the other BBSs.

The problem is the oil formulations. It's happening to EVERYBODY, and ALL MFRS of cams. These days, there's a chance that no matter what you do, the lack of the zinc compounds in oil will result in cam failure at startup.

The pit in the top of the other lobe is probably due to metal shavings fromt he rolled one.

Not much you can do, except try again; or go roller. Use Rotella T or other DIESEL SPECIFIC motor oil (although even those will be losing their zinc soon), and GM EOS.

Vader

That is excellent advice for anyone building a street-use engine any more.

Sonix

iTrader: (1)

Mine failed like that as well, 1000 miles or so, 4 lobes gone. I used EOS and 30wt dino oil. It was hard to fire up at first, that mighta killed it. Maybe it was not enough lube on the lobes, who knows. Had to rebuild the motor to get rid of shavings (all new bearings, gaskets, mostly time). If I was smart, it would have been cheaper to go to a roller cam in the very first place. But I didn't expect it to fail obviously so...
Was a lunati voodoo, now running a compxe, same break in procedure, this time it worked.

5678TA

i've spent soo much money on cam-related problems.. i coulda had 2 complete roller setups.. had 1-294s, and 2-306s cams.. all with lifters too.. $200 a set.. $600.. then i swapped to brodix heads.. came with roller springs which took down the 294S, bearings and gaskets.. also needed new pushrods.. then new springs were ordered and installed along with new bearings, gaskets and now a 306S.. that went down, with the bearings and gaskets as well.. so now i'm on my last 306S with yet another set of bearings and gaskets.. 3 cam and lifter sets, 3 sets of bearings, 3 gasket sets (not including intake gaskets for manifold swap,twice) and push rods and one timing set and new valve springs.. i spent over $2000 just on the valvetrain.. yes, i have a bit of bad luck with solid flat cams.. IF this one goes down i'm going roller..

_BANDIT_

Thank you for your answers. And I thought I was the only one with such a problem....

My friends here mostly modify and service European engines and were all amazed about what happened. Here in EU we don’t even know such malfunctions unless it’s a 300K miles old engine.
Can you offer me any suggestions? I liked this CompCams XE274H a lot, the engine was performing great.
If I switch to roller cam, what do I have to be careful about and which items do I have to replace? Cam, lifters, pushrods...?

Thanks again for your help!

Sonix

iTrader: (1)

Yea, normal engines don't wear out cams until that long, but fast ramp rate new style cams wear them out sooner. Like 100,000 miles maybe, but not as fast as you're seeing for sure.

I'd stick with another Xe274h. Return that one, you should get another xe274 free, you'll just have to buy new lifters. You'll want all new bearings and gaskets in the motor. I'd just try again, but be extra careful to do the break in to the letter. Use dino oil, with EOS or Crane Superlube or comps equivalent. Use lots of cam lube on cam and lifters, prime the fuel system so it'll fire up right away, etc.

_BANDIT_

[quote=Sonix;3201631]
You'll want all new bearings and gaskets in the motor. [quote]

Why do I need new bearings and gaskets?

Can you explain that in short, because I really don't see why that would be necessary.

Thanks!

Apeiron

All that metal that used to be a cam lobe went somewhere. Chances are there's some of it embedded in the bearings. The whole block should be torn down and cleaned up.

_BANDIT_

I thought that oil goes through the filter first and then to the bearings...

Apeiron

It usually does, but filters don't catch everything. When there's that much metal in the oil, chances are that some escaped.

Sonix

iTrader: (1)

Easy way to find out, you've got the cam out - stick your finger in where the cam was, and feel the cam bearings.
If they feel DEAD SMOOTH like new bearings, you're probably fine. Mine felt rough, which is a very bad thing for bearings to feel like. So I replaced all of my bearings. It's hard to reuse a gasket, so thats an obvious thing to replace.

EDIT:
If you want a good read...
https://www.thirdgen.org/forums/tech...?highlight=cam

You're at post #23 or so now... (Following in my footsteps that is...)

_BANDIT_

OK, I will try this tomorow (it's night time here now ) .
I hope they are smooth....

Thanks!

5678TA

do what sonix said for the bearings.. but i would just change them anyway because you dont want a new cam on junk bearings.. so, change all the bearings, all the gaskets, clean the block out REALLY good.. clean everything that can get oil on it from the engine (pistons, rods, crank, heads, oil pan, etc).. you dont want ANY pieces of metal in there besides the block itself.. and about the oil filter.. oil doesnt "flow" through cardboard (assuming you use a normal cheap oil filter).. when/if you try and get another free cam from comp, you MUST tell them that you broke it in correctly with all the lubes, special work and such that is recommended.. when my 306S went down i couldnt get a refund or exchange because i didnt take out the inner valve springs for break in.. (i can explain that at a later time).. if you still have the install instructions, read it and learn it..