IRONFIST

Hey guys, so I was to park my Trans Am for the winter tomorrow.. should have parked it a day earlier. Looks like I lost compression on Cylinder #4.. no idea how. Car did not over heat, the thing is pretty much baby'd. I'm hoping its just a head gasket, any other ideas?
This won't be the first time I've pulled a head off of a car, but the first time I've messed with a V8 made after 1979... How hard is it to get to all the bolts? Anything I should know? Any tools I might not have?

Thanks guys... I'm tryin to be optimistic, might be an opportunity to do some head work or get new heads.

conan

iTrader: (5)

Well if it had to happen at least you have all winter to work on it. The heads arent that hard to remove in the car. This might help you. http://www.ls1howto.com/index.php?article=3

massls1guy

iTrader: (9)

I would take off the valve cover on that side and take a close look at the valve train. Not sure what would cause a valve to hang open but that would sure kill the compression. It would be nice if it was fixable without taking the head off. Knock on wood for you.

Maybe also check your spark plug, make sure it didn't back out.

dankl

iTrader: (1)

Any smoke coming from your exhaust when you punch it? Have you checked your oil for coolant? If no coolant, probably not a head gasket. I hope its not a ring in your bottom end. That is what I'm going through right now. No cylinder pressure in #7. I get whitish smoke when I punch it due to burning oil.

Good luck, keep us posted!

IRONFIST

No smoke when I punch it, haven't checked the oil. I'm not sure what it could be. I want to make sure it is cylinder #4.. What's the numbering on the LS1, is it the same as the SBC?

Beaflag VonRathburg

iTrader: (176)

Bent valve, broken valve spring, dropped valve, etc... Pull the valve cover and look for obvious damage. That should be the first thing you do.

Randy WS6

iTrader: (69)

I had the same problem with my stock motor, and it was a broke ring landing but it could also be a bent valve.

crashinaz

iTrader: (35)

Leakdown test and form a plan from there.

IRONFIST

Leakdown test? Never even thought of that.... That should narrow it down for me.
Being that it's the last day of the month, I got way too much to do to even take the thing apart.
Just popin' the hood on this car makes me wonder how I'm going to reach anything...
I'll pull the valve covers tomorrow, if that doesn't show anything then I'll go with a leak down test.

Scoggin Dickey

iTrader: (34)

It's the same. #4 would be the 2nd from the front in the passenger side

8--7
6--5
4--3
2--1

IRONFIST

Yah it's #4 then that doesnt got any compression.