1963Corvette

Took my '63 corvette for service, thought it needed a new cam. Guy calls me & says that after taking the engine apart, the cam did indeed shear a lobe and that he saw metal shavings & said the engine needed to be sent to an engine shop for inspection.
Engine guy says, "after inspection, engine needs a total rebuild, including heads."
After total rebuild the engine was back at the shop and reinstalled. Repair shop couldn't get car running right, repair shop takes whole car back to engine shop, engine guy says exhaust manifold needs to be resurfaced to better fit on engine.
A few days later the car is back at the repair shop, who calls me to pick it up after 8 weeks.
Took the car home and over the next 10 days babied the car & drove mainly on roads with speed limits of 50 or less. After less than 300 miles, we got on the freeway intending to go one mile. The car struggled after reaching 65mph, the exhaust sound changed in the side pipes & as I let off to pull over, a large puff of smoke came from the hood & I coasted to the side of the road.
Happy 4th of July. Had large puddle of oil & oil poured from passenger side side pipe when vehicle was winched on to flatbed. Had car towed back to auto shop on Monday.
Engine was removed & sent back to the engine shop (1 year 12,000 mile warranty).
Engine guy says, "took the engine apart, it has at least one bent valve, which crashed on a piston head & damaged the cylinder wall."
Engine guy says I must have either revved the engine too high (excessive rpms) or incorrectly shifted the transmission since this is the only thing that could have caused this type of damage to the rebuilt motor.
When I told him that I was the only one who drove it & at no point did I ever excessively rev the engine or incorrectly shifted the transmission, he calls me a liar & says there is no warranty because of what I did to the car.
When I bought this car last year the engine had been totally rebuilt a few years back & less than 5k miles had been put on it.
Can anyone help me from going insane & suggest what could be the actual cause of this engine failure? I would deeply appreciate any input.

Frankie the Fink

If you bought the car a "few years back" and it had been recently rebuilt can we assume it was running fine until you thought it had cam issues ? Not that it matters much now but maybe that was the first step on a downward spiral. Wiping a cam in a previously good running engine in any fairly stock small block Chevy is a rare event.

Then, I can only assume that the engine shop was bad-to-incompetent....if you treated the rebuilt motor as cautiously as you say you shouldn't have had a catastrophic meltdown. I really wondered if you had a bent valve (pushrods usually go first) or the shop failed to put the valve stem 'keepers' on correctly so it dropped into the cylinder. Hard to say at this point.

Guess you have to play it where it lands. I'd take one more run at the shop for a warranty repair and also contact your local BBB (Better Business Bureau). Sometimes that works and if the engine shop is a chain you can work your way up the management structure. I had a ****-poor rebuild of a '66 Mustang automatic transmission back in 2006 by Coffman Transmission. The above strategy worked and they fixed it on their nickel.

I would head down to that shop with my cell phone and snap pictures of EVERYthing; particularly the damaged areas. You may find they used incorrect or cheap components and you'll have a record in that case.

Short of that I guess you could 'lawyer up' but that can really get expensive and nasty.

MikeM

Your engine guy would be seeing me either behind his building or in small claims court if you have the paperwork to back your guarantee.

Over revving is one thing that will cause a valve to drop but not the only thing.

After you go blue eye/blue eye with the engine builder, I'd find me another shop as he'd never get close to my engine again.

Joe Inama

Take it to claims court. Most times the customer will win with proper documentation. Have another engine shop evaluate the engine for cause of failure. That info is most times very helpful to yourself and the court. Good Luck

Bluestripe67

Welcome to the CF. If you went in and told them "you thought it needed a new cam". At that point that was a mistake giving them the opportunity to go wild in my opinion because of what you said. What basis did you have for that? Most issues with these cars can be resolved by looking at the fundamental component/issue. It may have only been a tune up of rechecking the solid lifter valve adjustment, timing and carburation. The series of events tells me one or both, especially the machine shop is incompetent. I hope this turns out better than it started. Dennis

Frankie the Fink

BTW - To the OP: you've double posted this thread...you should get the moderators to delete the other thread

Easy Rhino

Oh man, sorry for your troubles.

The story smells like the shop may not be suffering from excess quality. Lots of bad indicators in your tale. A cam "sheared" a lobe, not very likely if it was running okay when you took it in. Also, the shop "can't get in running right" and the fix is to resurface the exhaust manifold? B.S. - that nay make it sound like crap, but it can be tuned to run right with an small exhaust leak. I absolutely would not let this shop touch my engine.

What rpm did the engine reach around town before the open highway, and at what rpm did it let go? Valve to piston contact requires the timing to get off on an interference engine (e.g. timing chain failure), or the piston/rod to let go (rod failure), both catastrophic failures not logical on a new engine.

I would strongly consider getting your car/engine away from this shop and have a pro look at it. Your shop will figure out that you're on to them and protest, but you may be out a new engine anyway, sorry.

64365coupe

When the valve "crashed" the piston and either cracked it or punched a hole in it. That's how the oil got into the side pipe.
Maybe the exhaust guides were too tight and the exhaust valve galled in the guide and hung open causing it to hit the piston... But over rev? I guess it could happen if you were running the hell out of it but at that point it would take low valve spring pressure to boot.
Get the heads and ship them to me for an honest inspection. No charge. Damn... how tuff is it to build a good 327.
Good machining ,cleanliness and some experience. Steve

Frankie the Fink

Hmmm....or maybe that new cam grind was off....solid lifters are unforgiving. We'll prob never know...

1963Corvette

Thanks for the advise. I still have to retrieve my engine & figure out how to proceed. I may take you up on that offer.

ChattanoogaJSB

Sounds like a good shop to have your muffler bearings replaced at. I would pursue damages but in NO event would I leave any property with them.

bluestreak63

Where are you located and who was the engine builder? Maybe someone knows of him or possibly had an experience too.

1963Corvette

Thank you for the quick reply & advice. Trying to figure out what to do.

1963Corvette

Thank you for the quick reply & advice.

1963Corvette

I am in Michigan.

1963Corvette

It was around 3000rpm when it let go. I'm getting it out of there as soon as possible. Thanks for the advice & reply.

1963Corvette

They put in hydraulic roller lifters & cam, but did not change anything on the heads.
Not sure if he needed to to accommodate this.


Thanks for the reply

JohnZ

Roller cams generally use much higher valve spring loads than flat tappets do, due to the much higher flank acceleration rates on the lobes; a roller cam with flat-tappet springs would float the valves at a much lower rpm than the correct roller setup.

1963Corvette

So do you think that not matching those components could cause the problem?

JohnZ

Sure. Nobody with half a brain would install a roller cam and lifters without matching the valve springs to the cam manufacturer's requirements.