gtaproject

I'm doing the intake manifold gasket on my 88GTA (305 5-speed) and have a few questions. First, when I lifted the valve covers to change the gasket, I notice a deep dark black film (oil) covering everything . Not really glops of sludge, but it looked like everything had been painted gloss black. Same thing in the lifter valley under the intake manifold. The car had been sitting for about 6 years before I got it. Does this need to be addressed while I have everything apart, or will this all flush out after I get the car back on the road and do my first oil change? What would one use to clean these areas (assuming it should be done while I have the manifold off)? Should I run a "motor flush" through there after I get her running again, and do an immediate oil change after letting that run through the system?

Second, and I just want to be clear on this. When I put the intake mainfold back on, am I putting a thin bead of black silicone around the ports on both sides of the gasket? Does that mean, block, silicone, gasket, silicone, manifold? And, should I be using black silicone or some kind of "gasket sealant" around the ports?

As always, thank you all for you help. The wealth and breadth of knowledge of third genners (and availability of parts) was the main reason I decided on a 3rd gen as my first restoration project. This board has been most helpful. Thank you all.

todd200

I don't really know what to to tell you about the black film. The way you describe it, it just sounds like old oil. Have you started it or driven it since it sat for six years? If you haven't change the oil BEFORE you start it and put a little oil down the spark plug holes and turn the engine over by hand first. If you have started it, change the oil anyway. Change it rather often for a while and run synthetic to help clean it out. This is based on it being old oil and not sludge. Hard to tell without a pic. As for your intake gaskets I only put a little silicone sealer on the smooth parts of the heads to help hold the gaskets in place when putting on the manifold. Use a 1/4" bead of sealer on the front and rear of the block.

Vader

Project,

As for the oil film, if it is truly only a film of old varnish, regular oil changes should help clean that up. If there are any deposits of sludge in the engine that are accessible now, you should clean them now as best you can. Make sure none of the debris falls into the oil returns and sump.

When reassembling the intake to the engine, your primary need is to clean the surfaces as best you can. The aluminum intake should clean up easily and the iron may only offer a little more resistance to releasing the old gasket material. the only reason you would need to use a sealant on th eintake gaskets is if either the head or intake has some pitting around the coolant passage openings. If so, lay down a thin bead of sensor-safe RTV sealant around the opening(s) and install the gaskets. If both the head and intake have pitting, place a thin bead on both surfaces. Do not use any sealant around the intake openings.

For the ends of the intake, I've had good success with the factory "China Wall" seals between a thin layer of RTV.

Again,the big key in getting a good gasket seal is cleaning the surfaces. I usually scrape away all I can, then use a wire cup wheel in a die grinder to buff the surfaces to a mirror finish (just like what the factory had to work with when the engine was newly assembled). No runs. No drips. No errors.