Major Oil Leak From Top End of engine: 1992 OCC

Hey all,
So my 1992 OCC had a bit of an oil leak and would leave a small puddle on the ground overnight. I got tired of it and tried to fix it myself, by determining that it was likely coming from either the distributor gasket or intake manifold rear RTV seal. I replaced both myself and made the problem quite a bit worse (silicone newbie). After that attempt, I took it to a local shop for them to redo the distributor/intake gaskets properly. Just picked the car up from them tonight and it’s still leaking the same amount of oil that it was after my botched attempt from the same area.

So I’m wondering, is there any other spot that I could have disturbed in my attempt to replace the dist./intake gaskets that would cause this leak? I can’t think of any other spot, and I can clearly see fresh oil all over the top of the bellhousing and the top middle of the firewall.

In any case, I can’t believe that the shop wouldn’t have noticed that the leak was still present after they finished as they had to run the car to bleed the coolant system, etc.

Check the oil pressure sending unit.

On my car the oil pressure sending unit is down near the filter.

All 91-93s have the sender in that place. The OCC uses the sender for the gauge.

Fred Kiehl wrote:

All 91-93s have the sender in that place. The OCC uses the sender for the gauge.

Any thoughts on my issue Fred? You seem to be an expert on these cars haha. Is it possible the intake could have been warped or something could cause the distributor to not seal? I’m giving the shop a call tomorrow morning.

There are lots of things that can go wrong with replacing an intake gasket in the car. The tapered sides make it hard to set the manifold down nice and evenly into the silicone on the end seals and if you lift it even a bit, you can have a leak.

If you did it without removing the valve covers, you could have an issue with hitting the cover or valve cover gasket as you set the manifold in.

The corners where the intake meet the heads are notorious for leaking on many brands of intakes that are tapered.

Even if doing it on an engine stand, you can mess up and have a leak.

I have switched completely to "Right Stuff" sealant for all the silicone seal areas as it is very much superior to other silicones from what I have seen. I rarely get any leaks or issues with it. On the manifold ends, let it sit for a few minutes to firm up a bit before putting on the manifold but not long enough to skin over.

I really hate doing them in place, especially on the ones like the wagons where the back is under the firewall and it is a long reach from the sides to even set the manifold in place.

I designed a tool to place the intake on the engine with the engine in the car. It has an insulated pad and rotating arm that allows you to gently and precisely place the intake on the engine. I have a few for sale. A short stud in opposite corners helps alignment, and using some silicone to stick the gaskets to the heads keeps them in place during assembly.

booster wrote:

There are lots of things that can go wrong with replacing an intake gasket in the car.  The tapered sides make it hard to set the manifold down nice and evenly into the silicone on the end seals and if you lift it even a bit, you can have a leak.

If you did it without removing the valve covers, you could have an issue with hitting the cover or valve cover gasket as you set the manifold in.

The corners where the intake meet the heads are notorious for leaking on many brands of intakes that are tapered.

Even if doing it on an engine stand, you can mess up and have a leak.

I have switched completely to "Right Stuff" sealant for all the silicone seal areas as it is very much superior to other silicones from what I have seen.  I rarely get any leaks or issues with it.  On the manifold ends, let it sit for a few minutes to firm up a bit before putting on the manifold but not long enough to skin over.

I really hate doing them in place, especially on the ones like the wagons where the back is under the firewall and it is a long reach from the sides to even set the manifold in place.

It certainly sucks to do it with the engine in place. The shop doesn’t seem like they want to accept that they made a mistake but I’m bringing it back on Friday and hopefully they’ll do the right thing and redo it.

Fred Kiehl wrote:

I designed a tool to place the intake on the engine with the engine in the car. It has an insulated pad and rotating arm that allows you to gently and precisely place the intake on the engine. I have a few for sale. A short stud in opposite corners helps alignment, and using some silicone to stick the gaskets to the heads keeps them in place during assembly.

If I end up having to try it myself again I’ll get in touch with you about one of those tools.