weinerschizel

My cam gear fell off and I was wondering if anybody else out there has had a similar mishap with their LT1.

I would like to know what all breaks on these engines when that happens? Are there any serious clearance issues with the valves and the pistons w/o the cam spinning?

As of now I have the timing cover off and can see all kinds of shredings from the timing cover in the oil pan Four pushrods are bent on two cylinders as well.

Thanks for the help!

RE AND CHERYL

At the least your gonna have to pull the oil pan to clean out the shavings and replace all the push rods.

Good luck

BradZ28

My timing chain broke about 6 months ago. The stocker just snapped at about 3000rpm. I had some piston/valve contact and chances are you did too. As long as it's apart you should at least pull the heads to check the damage IMO. I got lucky as I had small marks on my piston tops but didn't ruin anything including the valves. Looks like time for a heads/cam package.

madwolf

Brad,
how many miles did you have on your stocker?
I put a cam in my car and a new stock chain with new sprockets... hopefully I'll be alright.

On a different note, Andrew Mattei also broke his (picture) and he temporarily replaced the engine with a monster.

BradZ28

Madwolf-I had 52K on the car.

Don't get nervous though, I think the reason it broke is because I had an underdrive crank pulley (BBK) and didn't know to use the stock balancer in front of it. With nothing to absorb the vibrations I'm pretty sure the chain couldn't handle it. I kicked myself for that one.

Other than me I've never heard of a LT1 timing chain breaking. yours should be fine.

Brad

weinerschizel

Thanks for the help!

Sounds like I will have to pull the heads then
Mine shut down at 5500 rpm... but we heard nothing. It was just like I turned the key and shut the car off. However, it made noises when I tried to start it back up. I think what we were hearing was the timing gear grinding up the timing cover.

BradZ28

When my timing chain let go it busted up my timing chain cover pretty good also. Make sure if the chain or gears did break up you remove all the small peices in the lifter galley and oil pan if they made it that far. You don't wanna spin a cam bearing if a small peice of timing chain get caught in there. Time to build it better and faster!

Brad

LT4Firehawk

I broke the timing chain on my 95 Formula while roadracing at 6000rpm several years back. Bent two valves and put a couple of scratches on some pistons, but otherwise everything was fine. You do need to pull the heads to check everything.

weinerschizel

What all did you guys replace when yours went out?

I have the top end of my engine appart. All of my exhaust valves hit pistons. However, only one appears to have bent.

Did you guys take the valves all appart and inspect the guides seats, etc? What all did you end up replacing? Did you replace the seats, valves (that didn't bend), and guides? Or just the stuff that was obviously broken?

I went to a machine shop to look into rebuilding the heads with new guides valves etc. Just to repair the exhaust I was looking at around $300 - $400. Is this absolutely nesisary?

Thanks for the help!

weinerschizel

Should I have my pistons checked for cracks? They have some nicks on them. Did any of you guys have troubles with cracked pistons? Is there anyway to tell when the piston is in the car?

Thanks!