Shurshot

Figure I would start a new thread and make the current situation easier to follow

I pulled the valve cover after I could not find anything wrong in the exhaust and that is when things became a little more transparent.

For sure the #2 intake solid lifter is collapsed so I am going to pull the intake manifold and pan tonight to try and get a handle on the extent of the damage.

Hard to believe that with my now tuned old 850 DP on last night in place of my problem plagued 950 QFT that my car ran better than it ever had, even with a lifter already starting to fail

I guess that banging sound that I heard was the start of the lifter failing ........ oh well things can always be worse

Ever hear of Sulivan's law?....... simply stated it says that Murphy was an optimist

Maybe it will not turn out to be a total failure and all those little needle bearings will be in place and accounted for...... that would be some good news about now

I will update this later tonight

Thanks for all the replies and advice on the other thread

Doug

Tintin

Man , what a drag.. That is what happened to mine too and when the cam gets de-lobed you have to hit the machine shop because you cannot get the metal out, no way. What a shame for you, sorry..

Sky65

A "solid lifter" can't "collapse". If the valve isn't opening it's far worse than that. Here are some pics of a friends solid roller cam and lifter. Just happened about a month ago. Not pretty.

The lifter on the right lost it's needle bearings.



Here's the cam.

67vetteal

No doubt it's the Cam. What were the break in proceedures and Oil used? Sorry for your problems. Keep us in the Loop. Thanks, Al W.

midyearvette

sorry dude.........is the cam button still there?...is the lobe next to it rounded off too?

Mossy66

That sucks out loud! Damn.

Gerry

AZDoug

The instructions that came with my Comp Cams retro rollers said to clean off the lube they were shipped with and dip in some other stuff, prior to assembly, to my recollection.

I would get a can of GM EOS and dip the roller part in that that prior to install, which is what I did.

You want good, high pressure, sticky lube on those rollers at first fire up.

Doug

Shurshot

The lifter was very difficult to get out and that was enough to tell that the situation was pretty bad.

Anyway the solid roller lifter has disintegrated so the cam is definitely wiped.

On the second build with this motor I had good spring pressure but not IMO excessive...... 260 on the seat with new springs and titanium retainers however I only had Comp Cams super pro lifters and that is what failed.

Lots of garbage in the oil so the whole motor has to come out. I just got the bloody car back on the road in January...... if I thought I would be happy with my 427 in it I would stick that back in there.

Maybe I should do that anyway but if I do then I will probably get rid of the car.

Doug

Frankie the Fink

So, in your opinion, did the hard runs with your rebuilder:

1) Make matters worse
2) Didn't change a thing

I was wondering about the wisdom of that (although I might have done the same thing)....I've been in the "dammit - break if you're gonna break mode" before.

Shurshot

Trying to be prepared the future there is the other way of looking at things of" better safe than sorry "....... but that is not what custom motors are about.

Had I not taken that ride there might not be roller needles all through my motor but in hindsight the only thing that I could have done to check for a "soon to happen catastrophic failure" that I did not do would have been to have drained and strained the oil....... and had I done that I am not sure that anything would have shown amiss before the roller disintegrated.

I went to bed that night quite confident that my problem was in the exhaust itself being as I had just checked the compression as well as just had the valve covers off two weeks ago for valve adjustment and every thing was fine.

However thinking back to when I just did the second build from the detonation of the first build and noted the very poor valve train movement from weak springs, I should have had the rollers rebuilt but I did not because there were only about 1500 miles on them. So if I did make a critical call in error I believe that is when I did rather than take it for a ride that I hope to be able repeat in the not to distant future as far as fun and making horsepower goes.

Doug

midyearvette

if your lifter bores are worn out, that will cause a roller to ride crooked on the lobe and cause a catastrophe. too much play will wipe a flat tappet because it causes the lifter not to "spin" and the lobe rides in the same spot and eventually wipes. lifter bores are overlooked so many times and are a most critical issue, this is especially true on a used or so called "seasoned" block.......

Shurshot

I agree that lifter bore is critical however these were roller lifters that do not spin......... but in hindsight shoulda had a rev kit.

Doug

Edit: Because I had shaft rockers I went without a rev kit.

AZDoug

What would a rev kit have done for you in this case?

Doug

muncieman

This appears to be a full on roller cam, not a street roller. 260 pounds of seat pressure, must be over 600 open or more.

You drive the puppy on the street???? I would check some of the springs and see if any broke or are getting weak.

PAmotorman

that is a cast roller cam not a hardened one so that could have caused the problem.

DansYellow66

Doug - Sorry to hear about the damage. I was hoping you would find it was something minor.

Dan

62Jeff

Based on some of the replies, it looks like some are seeing Sky65's pictures of a friend's damaged cam, and believe it to be Shurshot's cam.

Shurshot

My lifter is "very collapsed" and makes that one in the picture look like it is brand new. I also had a steel billet cam...... God willing I will bring it home tomorrow and get a picture posted.


AZ Doug asked
I really do not know as I have never seen one. It is my understanding that they are used for geometric alignment but the type of failure I had is quite common in solid rollers used on the street with the blame falling on the lack of oiling that becomes an issue at lower rpms. Consequently they are known to hold up better in race environments better than they do on the street. I talked to a man today who came highly recommended and is well known amongst the top builders in the country who told me that the low RPM and resulting low oil pressure associated with overdrives WILL kill the type of solid roller lifter sold by Comp Cams (and made overseas) that I was using. In the other thread I posted on how I had just gotten off the freeway (and using my OD TKO 600) and that when I cane to the stop sign I heard for the first time what I now know was a death rattle in the making...... BTW I did not mention to this man how and when my motor failed but it was him commenting on guys in corvette clubs doing long freeway rides at low rpm thus killing all but the best of solid roller lifters........ Unfortunately Comp cams solid roller lifters are not considered to be be the best and especially the ones that I had. Comp cams does have some good lobe designs and I was very happy with my cam ....... just not with their lifters.

Muncieman said

You are right on with the 600 #, lift is 680 and duration @ 50 is 265. That pressure # was brand new and when first installed so I figure they are probably at about 250-255 after some use. I will be checking everything and everything will have to be completely disassembled, thoroughly washed, dried and oiled. I did not get started today until mid afternoon but I do plan to finnish getting the motor out tomorrow.

Doug

PAmotorman

that is NOT a steel billet roller cam in the picture as it a cheaper cast iron roller cam that are not made for high spring pressures. a rev kit will prevent the roller from "skipping" on the lobe as it will keep the roller in the lifter in contact with the can lobe at all time.

Shurshot

That is not my cam in the picture.

Dan said
Thanks Dan....... I appreciate that as well as other words of condolences and well wishes both here on CF as well as in other communications.

It is good to be able to share both the good and the bad with others...... another plus here at CF section for C1&2 owners.

Doug