samgm2

Just killed my valvetrain.

While searching for my oiling problem, I carelessly installed my cam sprocket. I forgot that I had cranked the engine to check for oil flow through the lifter galley.

My cam was at least 15 teeth off.

Half the pushrods are bent and at least three valves aren't coming up. The damage appears to be to the intake valves.

I will pull the heads, but I am guessing the pistons are damaged too.

While we are at it, the timing chain appears to be stretched.

Maybe I should just shoot this engine and put it out of its misery.

It is going to be a while before this engine runs again. I am now looking for parts. Those who have them that aren't looking for big bucks, please contact me.

Sam.

Krab

iTrader: (28)

That sucks, sorry to hear that man. Hope the damage to the pistons isn't too bad, and you can get her up and running soon.

TigerFan187

iTrader: (1)

Damn it man! I am really sorry to hear that? Do you have a Z06 or just the motor? What year?

CharlieLed

iTrader: (1)

Nobody ever said an education was cheap...I think that we have all learned some very difficult lessons in much the same way. If it's any consolation, the '02 and later LS6 hollow stem valves don't like lateral movement and bend easier. Your pistons may not be as bad as you think.

TomsZO6

I am in sort of the same bolt if my cam was installed advanced one tooth off. The exhaust valves may have kissed my pistons. I will find out later this week when my installer takes a look at it.

samgm2

I have a 1990 Miata with the LS6 in it. The first Miata NA to get the LS1... Now dead...

I have a crate LQ7 that I may just throw in for now.

Would that motor be O.K. with an LS1 cam or a performance LS1 cam?

I don't have a truck computer. How would it do with the stock Trans Am computer?

Sam.

samgm2

There was no kissing with mine. 6 of the pushrods were practically folded.

Three valves are stuck way down and the springs wont pull them up. They appear badly bent.

I am going to pull the heads off in a few minutes to inspect the damage to the pistons.

Anyone care to comment on the likelyhood that my cam may be damaged? How about the lifters?

Sam.

Another_User

Wow...15 teeth is pretty careless. I didn't bolt anything down until I checked my timing chain like 15 times. That sucks. I hope there is less damage than you think!

samgm2

Yes, very careless. Its the first time I've done anything like this.

I am normally very careful and tend to over check things. The only thing I can think of is that the cam turned when I wasn't looking but I wont claim that I verified its position because I didn't. I just didn't think there was any reason to. I removed the sproket to replace the cam retainer. Pulled the sproket off, turned around, opened the plastic bag that the retainer came in and installed a keyed sprocket. Maybe the cam turned? Don't know. It will certain not be something I ever do again.

In the scheme of things, this is not a fun thing to deal with, but no one is dead.

The final tally:

Seven bent pushrods.
Seven bent exhaust valves.
Seven suspect lifters.
Number 1 exhaust valve broke off and hit jammed sideways into the seat.
Number one piston badly gouged and will have to be replaced.

I had pulled and disassembled the number two cylinder lifters and they had been cleaned of oil, so that lifter collapsed saving the pushrod and the valve.

I have a feeling the cam is alright but I will remove it and inspect it carefully.

Sam.

TigerFan187

iTrader: (1)

Sweet setup man! The LQ7 would be fine with a stock LS1 cam and even better with a performance cam-There is not differcence between a aftermarket LS1 cam and a aftermarket LQ7 cam-Everything is basiclly the same!

ZR2877

Wow a Miata with a LS6 in it. I bet that thing is wicked. I would love to see one of those. I bet it surprise the heck out of people. Sorry to hear about the loss.

samgm2

It was very fast. Without really hooking up, it did 0-60 in the low 4's at 6000' elevation. It weighed about 2500 pounds with the LS6 and a complete thunderbird rear end assembly.

Sam.