I am so happy to have found this forum. It has been useful to me many times already and as soon as I can I would like to help others. First, however I need to fix an oil leak.

I have a 4x4, manual trans. It's a 4 L V6 with about 180,000 miles.

I had the rear main seal replaced when my trans was rebuilt. The drain plug is new, the cap to fill the system is new, and I replaced the heater hose that connects near the top and put a hose clamp on it so I know it's not leaking from there.

Is there a good way to find where the leak is coming from? It seems to be a little higher up on the engine, because there is a lot of buildup (everywhere) but leading towards higher ground. Also, it seems to be pretty substantial, especially after freeway driving. I figure I add about a quart a week, driving about 300 miles/week.

Thanks for any information you can provide.

Kevin

 

These motors are notorious for valve cover gaskets leaking. You can try tightening them down but the only real fix is replacement. They have better gasket materials for these now so it should be a one time fix. I had a 91 and it was my driver's side.

 

I'd prolly also inspect the oil pressure sending unit; I've seen them develop leaks where the bakelite meets the metal.

 

Thanks for the tip guys. I hope to get a shot at it this weekend or next and I'll let you know what I find.

Are valve cover gaskets difficult to replace? And where can I find the pressure sending unit?

I haven't owned this car for too long but have already replaced the exhaust, starter, battery, plugs and wires and have been near covered in oil and gunk every time b/c of this leak and would really like to fix it.

Thanks for your help.

Kevin

 

BTW, I don't know why 'exha*ust' comes up as a link...I didn't do that.

Kevin

 

The valve cover gasket on the driver's side was a couple of hours job. IIRC, I had to remove the alternator. Not a big deal but added some time to the job. I'm not sure if A/C compressor interferes with the passenger side. You should be able to tell by looking at it. All in all a relatively simple job not requiring any special tools. I have not replaced a pressure sending unit but I would imagine that it would be available at most auto parts stores.

BTW-the links are automatically added based on certain words in the message. You didn't do anything but type the word. Same thing would have happened if you had typed tire$ and a number of other words.

Good luck.

 

I had the same valve cover gasket leak problems - after 210,000 miles the old gaskets were toast. I paid a shop to replace them, and it was 2 hours of shop time. One side is easy, the other's a pain.

 

While I'm doing this, is there anything else I should look for or do while I've got it all apart? I looked up how it's done in my Haynes manual, and it doesn't seem all that complicated but while I'm in there and dirty, why stop there if something else could be done with a few extra minutes...

I still haven't verified that this is the leak source, but I will before beginning. Could the cylinder head gasket also be a leak source? If it is, taking the valve covers off is part of replacing the cylinder head gaskets so I might as well replace them all if possible.

I am not 100% knowledgeable about engines - most of what I have learned has been from just opening the book trying to figure things out and now from this board which has been extremely useful. I guess I know enough to be dangerous, as they say.

Anyway, I really appreciate all the information.

Thank you.

Kevin

 

I don't think a head gasket would leak oil, but if you are going to pull the heads you'll need new intake and exhaust gaskets too. Don't even think of reusing the old ones.

 

OK, so you are going to do the valve cover gaskets and want to know what else you should do while in there? Leave the head gaskets alone unless you suspect a problem.
BUT Go ahead and remove the lower intake and replace the gaskets now. It is possible to have a oil leak from the front/rear of this too. Other issues with one this old is air leaking into intake at the center cylinder ports causing pinging, and water leaks around front/rear head passages if gasket deteriorates.
Some tips for consideration.
1. Plan on remove the following to make things easier. Upper intake plenum (leave the injector rail mounted to the lower intake), alternator. air conditioning compressor (loosen from mounting to allow some movement (but do not disconnect lines), coil pack.
2. The surface on the bottom of valve cover is totally flat (no channel for the gasket to sit inside) so plan on needing to adhere the gasket so it doesn't slide around at installation time. I use 3-M weatherstrip adhesive to "glue" the cork gasket to the valve cover side surface, then use silicone sealant on the head/intake side. If you do not glue the gasket, it will "worm out of place" as you tighten the cover bolts down, and you will still have an oil leak when finished.
Once you get all this other stuff out of the way, you can also easily change plugs and wires if necessary, as it is easily accessable now too.
Jut my 2 cents worth.
Dialtone

 

Well I replaced the valve cover gaskets. It took several hours - mostly to disassemble - reassembly was only about 30 minutes once I knew where everything was and had freed all the stuck bolts.

Here's the bummer. It still leaks oil, although it doesn't appear to be coming from any of the valve covers.

What about my oil pan gasket? A friend of mine suggested that as another source, and was wondering if anybody else had replaced theirs or found it to be a source for their oil leak. I have about 180K miles. The bummer is that replacing the gasket requires removing the engine. At least the leak will be gone!

Thanks for your advice.

Kevin

 

Kev -

I don't know if this is related to your leak or not, but it might be something to look at. My '96 EB 4x4 developed an oil leak. The shop I took it to said it was the timing cover gasket that was leaking both oil and coolent. They said that they would need to pull the motor to replace the gasket and the oil pan gasket.

If it turns our to be your problem & you find a fix, please post.

Thanks