SEA4

When I bought this car I noticed some traces of oil on the rear of the block..nothing major, no fresh drips on the driveway so it is not a bad leak.. I figured I would have to do the intake gasket 'at some point'.. Well, that some point turns out to be now

I had my car up on a lift today to replace the starter and noticed a fresh drip of coolant under the front crossmember.. my first thought was waterpump, but noooooo.. after carefully tracing the stain up the block I found fresh stains and some coolant right up where the drivers side front intake manifold bolt goes into the head.. that front corner has some dark green staining that goes towards the rear for a few inches as well.


So now I am gathering all the information I can on replacing the intake gaskets. I've done this same sort of job on a 3.0 Taurus SHO motor, but as 'fun' as that was, it didn't involve taking a distributor out.. I've never done that before.


I'm going to try this job myself..It's only nuts and bolts right?


I'd like some recommendations for the best gasket set to get, and the best rtv to make the front and back seals with.. also, anything else that I might want to replace as preventative maintenance since I'll have a bunch of stuff apart.

Thanks..wish me luck~

CaminoSS

I am in the same boat as you. I do not have the time right now to do the job so I keep throwing in stop leak. It takes care of teh problem for a period of time and I know that this stuff is bad, but it is hanging in there.

You will probably get as many different opinions on gaskets as you would on asking about mufflers. Fel Pro and Mr Gasket are inexpensive and get the job done.

Just make sure that you mark the distributor alignment well so that when you put it all back you have an easy time.

Have fun and know that I am only a couple of weeks behind you!

65Z01

There was a recent post on doing the intake base gaskets & seals; do a search for my detailed response on the dist issue as well as hints on a leak free seal job.

VetteVet86

Are you sure that the leak isn't from the bolt itself. On some heads, the bolt holes in the heads are not blind, but go through into the coolant passage. If the gasket was previously replaced and the bolts were not sealed with thread sealant, that would cause a leak. Might be worth a check before you rip everything out. I know that you were planning on eventually changing it anyway because of the oil leak, but if that solved the coolant leak, at least you could address the (very minor) oil leak at the time of your choosing.

Just my .02 cents.

SEA4

Hmmm.. I had not thought of that.. I'll snap a picture of the area in question and post it after work.. maybe someone can tell me if that particular bolt has exposure to a coolant passage.. the manifold has some moisture up around that bolt, not just at the seam of the manifold and head so it is worth looking into for sure~


and also, thanks 65Z01, I've already got the information you posted copied into a Word document for future reference

65Z01

I use Permatex #2 on the bolt threads holding the base to the heads. And I chase the bolts & holes with a rethread die & tap.

For gaskets I use the FelPro Top End Gasket Set from Auto Zone.

Hope cleaning the bolts & retorque seals the leaks for you.

tequilaboy

Good excuse to upgrade to an aftermarket base.

I'd hate to pull an L98 intake again only to fix a leak. Its really not that bad of a job, but if you're going through the trouble might as well reap some benefits.

My intake has been off twice. Once to fix a coolant leak (I upgraded to SLP runners that time), and once again to replace the lifters (this time I upgraded to a bigmouth base and SR uppers while I was at it).

I should have upgraded the base the first time around.

Next time it comes off, better heads will be going on.

GKK

Use the "Right Stuff" for the china walls and get a high quality #45 torx bit.

There are over 40 torx bolts that have to be removed and a cheap torx bit will break eventually. Torque the intake bolts to 35 ft. lbs.

SEA4

Here's the pictures, but the more I look at it, the more I think I'll just dive in and do the job.. The car is 18 years old, I might as well freshen everything up and give the top half of the motor a good cleaning.

It's a good excuse to change the thermostat, water pump, belts and hoses and all that.. make sure everything is tip top for a while to come..



There's the bolt that has the obvious leak around it..




and here's the spatter that is showing up on the underside of the hood.. I wiped this all down and then drove 50 miles and it shows fresh spatter again.

Time to get dirty and make things right

65Z01

I think you're right.

BTW, blow off around the intake base to avoid crap falling into the valley; it's really messy picking junk out of there.

Also use an eye dropper to remove all coolant from the T-stat hole in the base. After doing that there were only a copla small drops of coolant in the valley.

Good luck and have fun...

caa5030

When I did this i used my old wet/dry vac. It worked well.

tequilaboy

Sure its not simply leaking at the hose?

I rigged up a simple cooling system pressure tester using the small coolant hose that runs from the back of the intake to the heater hose, a schrader valve fitting and a small 12 volt compressor with built-in guage.

When pressurized, it was clear that my upper radiator hose was leaking at the thermostat neck.

Vito.A

The intake on my 85 leaked when new. The dealer reapired it and it leaked again several years later. I would recommend the Fel Pro gaskets. I install them using Ultra Silicone sealer gluing them to the head. I also use the Ultra Silicone on the ends (China wall) and a dab on the tip of each bolt to seal the threads.
Make sure you turn the motor over to #1 top dead center (TDC) before pulling the distributor. This will make re-installation much easier.
Also, I agree with getting a very good (Snap on) Torx socket as I broke a Craftsman when doing mine.

sami85L98

Here is a good info with pics and detailed explanation of intake swap on vader's website.

http://temp.corvetteforum.net/c4/vader86/

excessive81

did i miss it i was all over that site and couldn't find the intake gasket swap...mini ram yes stock ...well no! good site thought for sure! i started this myself yesterday. not sure how far i will go before i start putting it back together becasue i am sick in the head. valve covers had to be pulled as i don think you will ever get the last four bolts out with out doing so. i planned on it anyway to install the felpro rubber ones but guess what i found already there!!!! and the hypertech coil, bigger rockers...some times you just get lucky i guess...lol

SEA4

I 'worked from home' today and spent a few hours in the garage getting things torn down..

I've done intakes before but never a TPI setup and I've never even pulled a distributor.. Things seem to be going well though, I'm taking notes, using little zip lock baggies, taking pictures of how subsytems should look before I pull it apart so I can reference them later.. So far, no stripped bolts or broken sensor/wires/connectors.

I've got the intake out of the car..I'm now removing the AIR system. Next, the valve covers will come off for reconditioning and gaskets.

I'm going to do some clean up while I've got this much apart, and I'm going to change the fuel injectors, water pump and serpentine belt while I'm at it as well.. Car is 18 years old after all.. Worth the preventative maintenance to not have to do something a month from now that would be easiest to do right now while I've got so much apart.

Here's were I stand





and here's the intake on the bench.. Going to take some work to get this thing looking new again





I'll post an update next time I get to spend a few hours with the car.. lots of cleaning needs to be done!


ps. Did I mention that I've got 4 new rotors, Porterfield R4S pads, caliper paint, and 4 brand spankin new Bilstein Z51 shocks sitting here waiting to go on as well ?

coupeguy2001

BTW, do not use a wire wheel on aluminum. If you do, you better buy the thickest best gaskets you can buy.

CentralCoaster

Too late. Hopefully it wasn't a heavy wire wheel.

Use a razor blade.

86PACER

That's what I said the first time I pulled the heads. That lead to a bunch of "might as well while I'm in there's" :

86PACER

Why bother trying to clean things like this yourself. PITA and you won't get it as clean. I gladly paid my local machine shop a nominal fee for them to do all this dirty work for me. While they did this, I degreased under the hood. Then I just picked up the parts which looked better than new and buttoned the motor back up. Just keep all bracketry, screws, and bolts at home with you. It's best to hand them bare parts with nothing for them to loose.