red88L98convert

I've been looking for another vette for a little while now, not sure if I was going C5 or C6. I don't really have a preference, just want a good quality used, unmolested car.
A friend of mine at the local MB dealership got a 'perfect' '01 MY MT coupe with 107,500 on the clock. Let me just say, this car is gorgeous and comes with a lot of various upgrades, primarily visual. The engine compartment is almost as clean as if it were rolling off the assembly line. I could go on and on, but you get the point.
So, I took it for a test drive yesterday morning. The car was warmed up and running beautifully. I had run it through the gears hard once and was otherwise just cruising it to feel for any drivability issues. Nothing. Just perfect. When I got to a red light, I turned off the tcs and when the light turned green, I proceeded through the intersection normally but rolled into it pretty good on the other side. When the rpm's were in the 5000 range in first gear, there was a loud pop through the exhaust like unburnt fuel in the exhaust and the car shimmied a little. Then the DIC read: Reduced power, check tcs (or whatever it reads) and the car died.
They came and got me and towed the car back to the dealership. I pulled the codes and the only one that really made sense was the 'no cam input' one and 'communication failure'. I can't remember the actual codes.
Long story longer, today they checked it out and said the cam shaft broke. Now, I have not spoken to anyone who worked on it so I do not know how they came to that conclusion. My question is, is this something that happens???? I've never heard of breaking a cam. I've grenaded engines before but never snapped a cam! In fact, I've raced for 20+ years and seen tons of carnage, and the only time I've seen a broken cam was in an engine who's block cracked after the crank split.
Anyhow....thoughts??
If the cam actually did break, I could probably get the car hella cheap and just replace the top end. I'm curious though if the cam breaking could damage the block?!?!

jackthelad

Never heard of a cam shaft breaking I have to say. When you look at one, it's hard to imagine, short of a cracked block and resultant flex. I would be wary of that engine I think. Of course it could be the timing chain or gears.

Is the LS1 an interference engine anyone know? If it is, walk away unless they do a complete engine replacement.

neutron82

better to happen on the test drive rather than right after buying it... I would probably stay away from it if you don't want to put some work into it, there's no telling what happened or how bad the repairs will be... if you want a reliable unmolested car I don't think it sounds like the one for you... I have never heard of a cam breaking in half either but anything can happen

LoneStarFRC

Broken camshaft?

red88L98convert

Yeah......I'm waiting to hear from the service manager to find out how they determined that. If so, that would be a first for me!!! I've broken a lot of ****, even flattened a cam or two over the years, but never broke one!!!

LoneStarFRC

Broken/damaged/failed/cam gear or chain (or both)? Maybe.

Damaged/failed CMP sensor? Maybe.

Damaged/broken CMP wiring harness (or connector/pins)? Maybe.

Broken camshaft?

coia96vette

First I have heard of a cam shaft breaking. I too have raced for many years and have done my share of carnage on the engines. If it did break that would have caused a bit more damage to the internals. You would have to tear it down to see. Good luck.

martysauto

As far as I know the factory roller cams are billet steel. Add me to the list, never heard one break. I have heard of the old cast iron cams breaking, but that's rare. The scenarios mentioned above make the most sense. If the timing chain broke it's very likely to have bent valves and maybe damaged the heads themselves. I wouldn't worry about the pistons.
Keep in mind, the dealer is going to fix it as cheap as possible and your average MB line tech isn't going to be to thrilled to work on it. I would keep looking!

kirt70camaro

Get the price down where you can buy it and fix it yourself. If you look around you can find a used engine for $1000-$1500 that runs good. If the motor is stock maybe just a cam sensor? Highly unlikely a broke cam.

red88L98convert

Yeah, the dealership people are all good friends of mine, I'm thinking that I might just buy it (if the price is right) and slap and build another engine. I was planning on buying and building another engine anyhow, but was hoping to have the car running while sorting out the other engine. If they can't get it running, I'll see if they'll let me have it for $3000 instead of the $10,000 I was going to pay if it was running.
Anyone got a good short block for sale?!?!

kirt70camaro

Highly unlikely they are going to take $3000 for it. I know a race shop that pays $5-6 for a clean roller. Here is a short block. http://ls1tech.com/forums/parts-classifieds/1759044-2003-corvette-ls6-z06-shortblock.html

Good luck and keep us posted.

red88L98convert

Well, they are going to fix it and then I'll look it over and see if I'm still interested. They haven't cracked it open yet, but they are thinking that it's going to cost them roughly $5,000 to fix it. I don't know how they came up with that number, since they haven't been able to tell me as of yet exactly what's wrong with it, I'm guessing that number is based on worst case scenario. They are looking at pulling the heads, checking the valves, replacing the cam and replacing the chain/gears. They said that the $5K is for the labor!! He told me the book called for 33 hours!!!!!! The look on his face when I told him I could have the heads off and cam out in less than two hours was priceless! lol
Anyhow, if the car is repaired and running properly, I am probably going to buy it in the $10-11K range......depending on what specifically happened to it in the first place. So long as there is no metal debris floating around in the engine from broken parts, I think it should be okay. Right??

red88L98convert

btw, Kirt, thanks for the link. I think that short block is sold, but there are tons of them out there for similar prices if not cheaper, so I'm not too worried about finding a good one.

mrlmd

Whatever it is, you're lucky it didn't happen on the way home from the purchase.
And they didn't try to blame you for blowing up the engine and make you pay for it?
After they repair the engine damage, does it come with any warranty? If so, that would make it a better buy if it's all repaired well. It would be nice if you could watch them fix it.

neutron82

33 hours for a cam swap!... for that much they could get a new motor, maybe that's what the worst case scenario quote is for... if the cam really is broken and you are going to buy it why not have them put in an aftermarket cam with all the goodies while everything is out

3boystoys

I'm seen GM engines round off cam lobes when a lifter hung up but never seem a camshaft break. My guess would be a valve spring or lifter failed. Take 30 minutes to figure that out.

red88L98convert

No, they weren't trying to blame me or make me pay for it.....they were super sorry that it happened while I was driving it. I'm friends with the owner and all the department heads and they're all good people.
So, I bet the service manager $5000 that the cam couldn't be broken, but he didn't want to take me up on it......too bad. I just got a call about the damage. It was the chain that broke!
Now, my next question for you guys is this: On a stock engine, is there going to be any valve or piston damage from a broken chain?

3boystoys

Most likely, it is an interference engine.

Quicksilver Vert 01

I would have some serious concerns about a MB tech doing the work on what is, most likely, an unfamiliar engine to him. There are special tool required to do it right; such as a timing cover alignment tool made for LS1 engines. Also, special care must be taken to install the balancer. A new bolt is a must, along with a very specific torquing procedure to make sure it stays on.

I think you would be better off buying the car "as is", at a discounted price, and taking care of the repairs on your own. Just my 2 cents worth here.

martysauto

buy it as is or walk. I wouldn't want a mb line tech working on my car. I doubt the guy it's assigned to wants to work on it either.
Quicksilver Vert made some very good points!
If you buy it as is, you can send the heads out for porting and a valve job or install better heads. Slide in a new performance cam and lifters, oil pump and a good timing chain. I would be surprised if the pistons are hurt.