Hi all,

In light of my misfortunes here http://www.camaros.net/forums/showthread.php?t=108716 I was hoping to read up on changing the head gaskets. I have a few friends with workshops I could take it to, but wanted to read up on all the steps and recommendations specific to chevy engines beforehand. (I understand that I may have to send the heads away to be re skimmed/machined)

Are there any guides, recommendations (gaskets/thickness) for changing/checking anything else whilst I have the heads off, and gotchas available on this forum or references online?

Thanks and Regards

Derek

If you think the heads may be warped, you best have them skimmed which will remove about 0.003". This won't make any difference to running or using your existing parts.

When fitting your heads, just make sure both surfaces are thoroughly scraped clean with a sharp blade and thoroughly wiped over with a solvent. I use wax & grease remover which is a paint prep, but acetone is stronger if you're worried and neither will leave any residue.

Make sure you have the correct gaskets and that they are placed the correct side up.
Follow the torque sequence but don't go full torque right away.
Start off with 20ft/lbs and in 20ft/lb increments until you've reached the torque specification.

One thing I do is then wait a few hours to give the gaskets time to compress/relax. Then I back all nuts off (I use studs) a 1/4 turn and retorque.

Run a bottoming thread tap though all of the threads to ensure they are nice and clean.
Use GM sealing compound liberally on the bolt/stud threads that enter the block. See you local GM dealer for a small tin of the stuff. Best stuff to use for sealing. Don't be scared when the sealant leaks a little during the first 1 or 2 heat cycles.

Adding to the above, If you are considering on increasing engine compression slighlty and this also improves piston to deck "quench pad" clearances, You could decrease the thickness of a gasket, depending what the current gasket it and your useage.
Since you have done a search on changing head gaskets, you can do a search on this subject or ask this group on suggestions. Please add your engine specs and application when doing so.

Thanks for your fast responses there, I appreciate it.

I will make sure I get all the parts/tools before starting.

I think I have all the torque specifications for the engine I have. Its pre 86 350ci with stroker kit to 383ci. I believe the car was used to race and so it has edelbrock Alu heads..

I notice from the history that there are receipts for Fel pro 1010 and 1094 gaskets. (0.039 and 0.015 resp.) The receipt dates are within weeks of eachother with the 1094s having the later date.

Whilst at it I have a new thermostat to fit...so may think about gasket set which includes thermo gasket and do inlet manifolds too etc.. I may check out the price of a bolt kit also

Sound's like maybe the .015" #1094's are in it to hyelp make a schosh more compression.

Won't know until you tear her down unless by chance you can get a look at part of each headgasket somewhere like up by the "horn" areas". I think our engine's head and block castings are kinda open in there??

pdq67

Usually you can see a corner of these gaskets on the lower side ends of the heads. Might give you a clue. The 1094 gaskets are the steel shims , the other is a composition, duh.

I think I may just go for the edelbrock gasket set should include all I will need for the parts that will be disturbed when the work is done. Just need to find the time to start it!

Remember to get her good n clean before you start. The less grunge on top of the motor, the less will fall inside when you pop the heads and manifolds.

Also, VERY IMPORTANT!!! The outside surface of the heads is LOWER than the coolant level will drain from the radiator petcock! To avoid filling your cylinders with coolant, drain the block by removing the drain plugs located in the middle of each side just above the pan rail.

And don't forget to change your oil and filter.

Also on the intake manifold end seals, don't use the gaskets that come in the set. I use RTV called The Right Stuff. It sets quick and is designed for making seals like this. Intake end seals are notorious leaks.

Thanks for the tips guys. Always good to get the lowdown as I am sure I would've been bitten by those.... I definitely dont want debris / coolant in the cylinders :sad:

Thanks also for the tip about the inlet manifold seals. I am about to place an order with summit.. so I read this just in time 1am in the UK now :-)

I just read your previous thread, I had an 87 IROC with the same problem. When you remove the intake look at the lifter valley on both sides. Mine had a crack that ran down the entire lifter valley on the pass side. It looks like a fungus growing out of the crack. Chevy had a service notice about this problem. I can't remember what years the notice covered but 87 was one of the years don't know about 86.
Greg

I figure that "fungus" stuff was probably dried waterglass that was in the coolant that got through the crack and dried over time..

pdq67