flyinace2000

OK GUys here it goes...I will replaceing my Head Gasket in the next 2 weeks with the help of some forum members (thank god). I am replaceing cause my old one blew. While doing this job what else whould i repair? Where can i buy a good replacement for this head gasket. And an other pointers you got i will take. O yeah if anyone lives in the Northern NJ area and wants to help you are welcomed. Thanks!

-Will

VetteNoob

Glad to see you are going to tackle this and that you got some good people up there in NJ to help you out. Dont have any recommendations as to what else to fix while you are there. Ill leave that for the guys that's done this before and knowswhat they speak of. Good luck on the project, take LOTS of pics for us. :smash:

The Rex

Congratulations! You're about to break your cherry! You should feel like Henry Hill when he first got busted for peddling cigarettes. Sure, it hurts at first. After it's done & running you'll be glad you did. Just make sure to have the heads tested when you pull them off. Other than that good luck. Be happy your in the Vette community to have some help. The ricers would tell you to get bent. :flag

Mez

You will have to scrub the block deck and heads to get off all the old gasket and carbon. I got a Rolock scrubber from NAPA made by 3M that attaches to an electric drill. It is a 2.5" diameter green disk with about a hundred .10" diameter nibs. It does a great job of removing old gasket material without damage to the heads or block or gumming itself up. Don't use any sharp object (i.e. putty knife) or sandpaper as these can gouges and early head gasket failure. The 3M gizmo is great at cleaning carbon out of the combustion chambers, too, for both iron and aluminum heads.

You should stuff paper towels in the cam valley and in the cylinders to keep debris from getting down there. But you will get some there anyway. Spray some WD-40 down there and use the shop vac to get most of it out. I soaked paper towels with lacquer thinner and placed them on top of the pistons, covering with plastic to reduce evaporation, to disolve oil and carbon deposits. I then rotated the engine a few times and wiped off any debris that was left by the rings on on the cylinder walls. Use the shop vacuum often.

Just to be safe, you should replace the head bolts. The orignals bolts may have damaged threads or stretched. You can order a complete set from your local Chevy dealer, but Scoggin-Dickey sells a set for about $26 delivered UPS or about 1/2 the price of my local dealer. The ARP bolts cost more (about $45) but some think they are worth it. If you engine is not modified, stock head bolts will be fine.

Run a thread tap soaked in mineral spirits down each hole in the block to clean out everything. This helps prevent false torque readings and leaks. Make sure you follow the directions and put thread sealer on the bolts since the bolts go into the water jackets and will definitely leak without it. The GM bolts already have thread sealer pre-installed, but a little dab more won't hurt.

You should also replace the intake and exhaust manifold gaskets. On my 1996, they came with a sandwich stainless steel and they worked fine. In my opinion, aftermarket gaskets are no better than stock.

The ends of the intake manifold where it meets the block should be sealed with black RTV available at any autoparts store just make sure it says sensor safe. Make sure the tube is fresh and very pliable as RTV if left on the shelf too long becomes hard. Put a very consistant 3/8" diameter bead on the block and let it squeeze out when you reinstall the intake manifold. I put too little on the first time and had to re-do it. I then loosely tighten the intake bolts, waited 24 hours before torquing them to spec. Don't drive the car until the RTV has cured 24 hours. Then recheck the bolts torque after a few days. I found a couple of bolts that had loosend up a little. I don't have any leaks after 6 months.

Good luck.



[Modified by Mez, 9:06 AM 7/14/2002]

ToniH

Hi, good choice to repair it and not sell. It is a minor repair anyway. :)

Keep the questions coming and you will get good answers. You should get the gaskets from almost any speedstore. Felpro is a good manufacturer. I recommend you buy a full top end kit and change ALL gaskets you take out (and even some that you don't ie. valve seals). Clean all parts well before puttin them back. Mez gave you some good advice, follow it. Especially make sure you don't drop anything into the engine.

Have a nice experience repairing your car.

ToniH


[Modified by ToniH, 10:50 PM 7/12/2002]

Fozzy_Bear

Hi.

First off, I am going to be pulling the heads off of my 86 at the end of the year, so be sure to post a lot of pictures < please :) >. When I pull the heads I am sure that I will simply not be able to resist doing a couple of things.

First, I will have at LEAST the ports gasket-matched, I will possibly have the whole port/valve job done. Lets face it, in an internal combustion engine, the cylinder head is where the magic happens. If I actually hold them in my hands, I could never just slap them back on the block. I have seen a few very good articles on DIY porting, but I don't want to spend the time to become an expert on machining, and I don't want the work done by somebody who is not an expert, so I will probably break down and pay somebody to do it. My father has a friend who owns a machine shop, so I can probably get a fair price.

Second I would absolutely change the valve seals. They wear out ( they are designed to) and you might as well do it when the heads are sitting on your bench. Besides, a new set is like $16.00 or so , I think.

Third, I am planning on stepping up to 1.6 ratio roller rocker arms. I don't want to go through the notable time it would take to replace a cam, but if you are going to have a valve job done ( and I want to ) they will have to remove/replace the springs and rockers anyway. Changing the rocker ratio is like changing to a cam with a 7% higher lift. Plus the rollers notably reduce the horsepower absorbed by the powertrain. Less power absorbed = more power to the road. I can't see them charging much (if any) more money to simply use buyer-supplied replacements when they reassemble the valve train, so this is also a no-brainer ( as long as the actuall material cost of the rockers is something you can handle).

Fourth, I figure that this is a perfect time to install headers. Since I will at the very least port the exhaust of the heads, I can perfectly match the headers to the heads. The thing with this is that this is the least likely to get done because I don't want to spend all my money in one week, and I figure that having the heads off will not make it that much easier anyway. So I may just end up porting the stock exhaust untill I replenish my toy (car) expense fund.

And Lastly, you can shave the heads. I am not planning on this, but you might want to consider it. A couple of passes on a milling machine and you can raise the compression rating significantly without touching the crankshaft of pistons. Of course you can over do it and cause your valves to contact the pistons ( GAME OVER, thank you for playing ). So you would absolutely want to do a lot of reasearch about that before going that route.

Or you could just plop down $1200.00 - $1800.00 for complete aftermarket cylinder heads and $800.00 for ceramic coated headers, and be done with it. Heck, why not another $2000 and slap a miniram intake with new injectors on top? And after that, you would need a new computer program, but they are only like $500.00 right? ........ Of course if that were an option for ME, I would have just bought a vette with less than 150k miles :D

- Fozzy

Mez

Once the wrenches start to fly, its definitely a slippery slope. When I removed my 1996 LT4's intake manifold to fix the classic oil leaks in the front and rear, it was too tempting to removed the heads and start porting and gasket matching. For the full story, visit my website in my signature.

I agree with Fozzy that while you have the heads off, replace the stem seals and check out everything else. A good machine shop does not charge that much to a 3 angle valve job and while you have it all apart, pocket port them, check the guides for wear, check for warpage, etc..

In the end, its well worth it.

STL94LT1

Will, with a blown head gasket there is a chance of a warped head. At the very least I would have the heads resurfaced.

Good Luck
MP

TheCorvetteKid

I'm actually going through the same job right now. I just started about a day ago.

Good advice on changing the valve seals and replacing the head bolts with new ones. Also, having the heads checked for both warpage and/or cracks is another item you should consider going. The last thing you want to do is bolt them back up and find it wasn't a blown head gasket but a cracked head!

Consider changing the water pump at this time too. It's easily accesable and not too expensive either.

Also, get a flat piece of glass and check to make sure your pushrods are straight (just roll them along the glass surface). Now's the time find out if any are bent. And these are pretty cheap to replace too.

You should also consider dropping the oil pan and checking the main bearings as well (depending on whether any coolant got into the oil). Coolant can destroy main bearings very quickly. If you decide to do this, just remember to check each main bearing one at a time (remove, check, and reinstall).

Beyond that, just take your time and be patient. Mez (above) has provided some very helpful tips. Follow them.

Good luck with it.

Mez

Glad to hear you are planning to get the heads thoroughly checked out.

A couple of other items.

You should drain the coolant from the radiator and engine block. The radiator has a plug on the passengers side. For the block, remove the knock sensors on each side from below.

When you have finished, change the oil just in case any debris or coolant has gone into the oil. Unless you suspect something is wrong with the rod or main bearings, I don't think you should drop the pan.

When you remove the valve train, make sure you clean all the oil deposits out of the rockers and push rods.

flyinace2000

Thanks all this is great stuff.

There was a decent amount of coolant in the oil so should I check those bearings?

-Will

scorp508

Somebody definitely should check them out.