Wierd oil leak

My 91' Vic is leaking oil on the tranny pan but I cannot find the source of the leak. It seems to be only leaking when the motor is running because there is no puddle or traces of oil on my driveway. I've changed the valve cover and head gaskets but am still at a loss. Any suggestions are welcome.

Despite having changed the valve and head gaskets, it may still be that problem. I had them done on my car by a shop, the job only lasted a week, i took it back and they did it again.

Again it only lasted a week. So i got them to pay for the materials and i did it myself the 3rd time (by now it was only the valve covers leaking) and it was good for a few years, though it needs done again.

I'd have it looked at again. The reason it had to go back was just poorly sealing the valve cover gaskets, ie. they didn't use the gasket and the silicone to seal then with the first time for some reason, and the second they didn't let the silicone dry long enough. Either of these can be the problem, also improperly cleaning the old gaske and sealant completely off the covers themselves, that can pose a problem with the seal.

That's all that i can give you....hope it helps.

Thanx for the info, but I'm almost 100% sure it's not the valve covers or head gaskets that are the source of the leak. The reason I say this is because there is no oil on the exhaust manifolds or the block. Maybe the oil pan? Whaddya think?

Nothing around the exhaust manifolds certainly means the valve covers are out!

It could very well be the oil pan, as you move and hit bums and that if the oil pan is loose that could be part of the problem. This can be cured by simply tightening the bolts that hold it on.

Unfortunately, that's all i can suggest, unless you're able to find the root of the problem. I'm guessing you do your own work to the car?

Check the fluid levels of both the tranny and engine. Its easy to distinguish one from the other on the ground, but if your undercarriage is dirty, tranny fluid will have the appearance of dirty motor oil. Last week I had to replace both transmission coolant lines to my wifes 98 CV. Where they run between the oil pan and the cross member, they corroded a little, and started to leak. Had tranny fluid sprayed on the oil pan and undercarriage, no dripping had started yet, but tranny started to act funny. Just dont let any fluids get too low. Good Luck!

Thanx for all of the suggestions. I think I'll try my luck with the oil pan gasket.

Again... thanx everybody for the info!

Look close at the oild pan. Ford has had a few problems with the pan corroding through. It won't leave a puddle, but the blowbly will we the undercarriage.

I have a 93, same problem. The oilpans rust through and leak like crazzy, be verry carefull but try cleaning it and use some JB weld epoxy to seal it, otherwise u need to lift the engine to reaplace the oilpan.

I also have a '93 where the trans coolant lines (reuturn line specificaly) formed a leak near the pan. I had the lines replaced last week and now the pan itself has developed a 1cm hole dead center from rust.

Parts guy quoted me $85.50 retail for a new pan but the labor will kill me. I am waiting for a local CV enthosiast (I dont spell) to contact me to see it it is worth the cost and effort to do the repair. My CV is a long term restoration project but I did not plan for this this year.:frown:

JB


BTW. if anyone has had the coolant line replaced as well did your mechanic replace the entire line from rad to trans or just patch arround the leaking section? Mine did and I had not seen this type of repair before and don't trust it. he used a shrot line and two joiners.:screwy:

Well, I actually did the fix myself, and I did the same thing. I scabbed in two pieces and it is still holding up today.

jk, Glad to hear it. I was worried that he did a botch job on my lines (he's a new guy, the son of my regular guy).

If it is not the oil pan then you might be looking at a rear main seal they are common on the old box 5.0s.