Hi Guys,

New to me 1990 club wagon 5.8L with 34k original miles .

I have an oil leak that appears to be coming from the front of the right side of the engine that is dripping down on the exhaust. I can see it is not the oil pan gasket and have tighten the valve cover gasket ( cork gasket with anti- crush bushings ) The problem is I cant see where it could be leaking. Is there anything in that area I should be paying attention to ( known problem spots ) in reguards to oil leaks ?

Many Thanks,

 

Are you talking passenger or driver side? And is it dripping onto the exhaust manifold? Or working it's way back to the exhaust system?

It's kind of difficult to diagnose a issue without even seeing the engine. If it's dripping onto the exhaust manifold that pretty much leaves the valve cover gasket as the most likely culprit.

 

Valve cover gasket most likely. Could be front intake but that usually puddles at the distributor. I think one side can be done with the intake on but the other side the upper intake has to be removed to get the valve cover off.

 

The leak is on the passenger side of the engine, towards the front of the motor. I am pretty sure it is dripping on to the exhaust manifold. the whole front right side of the motor is wet with oil and it is running down to the cross member. There is no puddling near the distributor. I just cant pin point it because I cant see what is going on in that area with all the hoses there...

 

Gotta be the valve cover gasket

 

I agree probably the val cover gasket.
Some tips from someone who just changed theirs last summer.
I bought the blue rubber metal frame felpro gaskets but if I had it to do over again I would have bought the Factory ford gaskets Part# F1ZZ-6584-B
I still had a small leak with the felpro gaskets. Their website mentions using aluminum valve covers so I called their tech guy and he assured me they would work fine, they didn't.

I am not sure if your plenum gasket is the same on the 5.8 as it is on my 5.0 but there was a problem with the fitment of the felpro and Ford gasket. Both fit the plenum just fine but did not fit on the lower intake very well and I had to enlarge the holes in the gasket in order to center it properly. I inserted a couple of studs into the intake to hold the gasket in place and help with lining up the plenum when I sat it down in place. No sealant is needed for the plenum or valve covers but due to the alignment problem with the plenum gasket, I just a little on the outer corners of the gasket to keep it from shifting around

Clean everything very goo and make sure there is absolutely no oil residue, old gasket, or glue left behind. the front on the passenger side is hard to see, I used my camera to view it better.

Make sure the valve covers are flat and clean. Sometimes there will be a indent where the bolts hold tha covers to the heads and you will need to use a hammer and socket to make them flat again.

I screwed a couple of 1/4" studs into the cylinder head to use as alignment pins so I could hold the gasket in place while installing the cover.

You dont want to have to do this again! I also put rags around the rocker arms and sprayed some brake clean around the edges of the cylinder head so there would be no oil or grease that cold contaminate the seal.





Below is what I am talking about on the plenum to intake gasket


Below is the closest I could get the gasket to fit after enlarging the holes so it could be moved around.



Hopefully yours will be the round oval holes.

Once you get the plenum and valve covers off you will be better able to determine if that is actually 44,000 on the van. Those odometers only go to 99,999 and roll over again to 0. It is quite common for sellers to tell you it is the actual mileage. hopefully yours is correct! It would be a great time to clean the throttle body and inside the upper plenum. You might be able to somewhat gauge the mileage by the buildup inside the plenum and intake. At 44k yours should be pretty clean.

Mine shows 117k and here is what the plenum looked like before and after cleaning



I took mine to the spray car wash and used the engine cleaner, high pressure spray, brake clean, and wire brushes to reach inside and clean it as best as I could.
Here is a shot of the inside.

 

Below is what I am talking about on the plenum to intake gasket


Below is the closest I could get the gasket to fit after enlarging the holes so it could be moved around.








[/QUOTE]
The internal gasket mismatch isn't a big deal, all the runners start in the same place anyway. What you don't want is the perimeter gasket portion not fitting and covering the edges. The 5.8's all had the oval port upper and lower, with the exception of the Lightnings

 

I completely agree.

If I have a bad mismatch on the divider gaskets I will try and trim them. But if they start looking thin I will just cut out the dividers. The main thing is I don't want the gasket hanging out into any of the runner openings. And I also don't want it to be to thin to where it could break off and go thru the engine.

This may not be the most popular thing to do but I also put a thin coat of RTV (not a bead! ) or gasket sealer on both side of the gasket around the perimeter. This makes for more clean up if I ever need to remove the upper intake. But I've never had any vacuum leaks when I replace the gaskets.