Well it finally happenned, after 204K+ miles the intake gasket finally blew out on me. I knew it was coming as I have heard that this is a common problem on L98. I popped the hood the other day to check the levels because it was running a little hotter than normal and saw coolant all over the back of the intake manifold and could see where it was seeping out from. Was not happy :nonod: .

Anyway I am changing the gasket this weekend was wondering if any of you guys have any tips on making sure that the gasket seals right. For the guys that have done this, did you use any kind of sealer RTV, or is it better to clean the mating surfices to the metal and just put on the gasket with no RTV. I have had bad experiences with sealers blowing out before on waterpumps so now all I do is clean the surfices real good and bolt it down tight with no RTV, haven't had one leak yet. Just wondering the best way to do it because I do not want to do this twice. Oh and how long should this take on average? Thanks in advance.

 

Clean the mating surfaces really really well. Then put a thin layer of black RTV on both sides of the intake gaskets. You also want to put a pretty decent sized bead of black RTV along the front and back edges of the engine block walls. When you pull the intake manifold you'll see how much the factory puts on (a lot).

I have a picture around here somewhere of how I did mine.....

 

Also...After you get the intake back on, DO NOT start the car for 24 hrs!! This gives the RTV front and rear seals time to set up.
:cheers:

 

I've done that job and would allow a weekend or several evenings.

Get a FelPro intake gasket set and some black RTV.
Clean all gasket surfaces very well with say carb cleaner; some guys even rough up the front and rear lands for better adhesion of the RTV.
Apply a thin coat of RTV around each water passage opening on the gaskets and lay the gasket onto the head.
Apply the recommended thickness of RTV along each land and immediately lower the intake base onto the engine.
CAUTION-do not move the base once it has touched the RTV as that may cause the seal to fail.
Tighten the base bolts to specified torque in the correct sequence in three stages.
Assemble the rest of the intake.
Let the job stand for 24hrs before starting the engine to allow the RTV to cure completely.

You will want a very good T-47 Torx bit for the intake base bolts and maybe even a new set of bolts. I managed to mess up seveal bolts with a cheap Torx bit.

Have a section of gas line hose and two hose clamps ready to seal the fuel lines, as they can tend to seep fuel forever.

Drain about 1-2gal of coolant and use an eye dropper and towls to remove all coolant from the theremostat opening. I did this and got absolutely no coolant into the valley when I pulled my intake.

Behind the dist area you will find a grn wire that goes from a "hidden" connector to the EGR temp sw atop the EGR tube. This would be a great time to splice in a piece of #22 ga wire to bring that connector up to the right of the dist for easy access should you ever have to replace that EGR temp sw. You will see what I mean when you disconnect the sw to remove the EGR pipe from the intake base.

Good luck.

 

I did mine last summer. It took a whole weekend plus a couple of days. I did a lot of porting work to the plenum and base while it was off. Porting made a noticible improvement in the "seat of the pants" feel. Take some digital pics as things are coming off. It will help greatly as your are putting things back together, such as, did this go over or under that etc. I also got a few tips about not moving the intake around on the block after it is set down. Moving it around will cause a poor set on the RTV and you will be repeating the job. Set the intake down exactly where it is going to stay. No wiggling.

Good luck and have fun.

 

Is there a difference between the black RTV and orange RTV? My brother used the orange RTV for my car. He didn't use the black RTV that came with the gasket.

 

I'd like to know this as well, I already have the orange/red? "heat treated" RTV, does it make a difference?

 

IMHO, FelPro says Black, so I used Black! I didn't want to take a chance with that job for the small $$ to buy a new tube.

 

True, I'd rather spend a little bit more and not have to do it again until the motor comes out this winter.

 

The red/orange, high temp. RTV cost more than the black RTV (I think). Beside the black RTV came with the gasket was too small. Hope I did mess up since it is done, just waiting to drop the engine back in the car.