Hi, I replaced my oil pan gasket, twice with two different aftermarket blue rubber type gasket from Advance Auto parts. It only leaks in the front of the oil pan where there the half round shape. I guess I can lower the oil pan an inch and clean up the rubber gasket, with ??? cleaner? Can I add silicon on the rubber gasket. Should I try a a cork gasket? Or a Ford gasket??

Would a bad gasket cause a low oil pressure reading, when under load?


Thanks guys

 

Are you sure the gasket is leaking, or is the front seal leaking down onto the gasket making it look like the gasket is leaking?

If the sealing surfaces were clean before you replaced the gasket, cleaning them, or the gasket again won't help. If the sealing surfaces weren't clean, then it might help. Cleaning the gasket itself probably won't help much.

Opinions vary on which type of gasket is better, some like the rubber, some like the cork. I've never had problems with either kind, but I'm picky about assembly. You can't be too clean and taking your time tightening them down never hurts anything, over torquing is bad.

If its actually your pan gasket leaking and not something else, and you have everything clean, there are a couple other possible things. You might have a gouge in the sealing surface, but its unlikely. Easy enough to look and/or run your fingers around and check.

A more likely possibility is if the pan had a cork gasket before and somebody over torqued it a lot. This bends the area around the bolt holes up. It will feel like round bump at every bolt hole. If you then use a rubber gasket with the metal spacers these bumps will hold the pan away from the gasket making it leak. Whenever I do a metal pan gasket, or valve cover gasket, or trans pan gasket, anything that isn't aluminum actually, I check for this.

Its easy to hook the pan on the edge of a sturdy bench and tap the streched metal back down with a ball peen hammer. Providing you can get the pan off that is.

If you can't get the pan off and your bolt holes are streched, you are better off with cork again. It will compress some, the metal spacers in the rubber gasket won't. If the holes are really streched you might consider a thin (very thin) layer of silicon rtv on the pan, block shouldn't need it. Carefully put it with your finger and spread it out evenly and let it cure for a good 15 to 20 minutes before you put the pan up. If you spread it evenly it will fill in slightly more in between the raised bolt hole areas and none on the raised part at all.

Don't over torque the bolts in an attempt crush the gasket to match the distorted pan holes. It will split the cork down the middle. Watch the gasket, if it starts to buldge out around the bolt holes when you are tightening it, stop. At this point you have gone too far, but it may be ok if you don't go any tighter.

Remember, you can always come back and tighten them a little more later if you have to, but you can't back them out later.

No, your pan gasket has nothing to do with your oil pressure.

You will want to check that with an actual screw in pressure guage.

Bearing clearance and oil pump condition are what gives you oil pressure. Condition and viscosity of oil also have an effect.

 

Thanks! The main seal is not leaking, still looks clean. The bolt holes are all flat, the pan ridge is ok. My rubber gasket has metal spacers at each bolt hole. I also have two 1/4" thick metal bars on each side of the oil pan, installed before bolts. Will the blue gasket silicon work for this application, or do I need high temp silicon? It had a cork gasket before, it was leaking at the front to.

I think my main crank bearings are worn. My new pressure gauge says zero under load, it reads good at idle. I also replaced my oil pump with a high pressure pump. It's been like that for 5 years, truck still runs well. ????

Mike

1993 f150 5.0 gas

 

Sorry, forgot about the metal rails on fords, not going to strech a bolt hole with those.

Couple of other things to look at, maybe the timing cover gasket is missing a chunk toward the bottom? There is an oil sending unit right near there as well, it might be leaking?

I use the high temp mega black silicone when I do use silicone. Couple of places I have used clear in the past, but not very often. I don't use a lot of silicone at all actually, but if you have a gap where the timing cover, block, and pan come together it would probably solve that.

There may be a difference which gasket type your pan calls for. I haven't run into an issue, but I work on everything and haven't pulled the pan on an older ford for probably 5 years, just don't see a lot of them in the shop. Newer vehicles are pretty much all rubber. Somebody here with more experience on these particular engines would know better than I if there is a difference in pan styles or something of that nature.

Offhand I would say to use cork if you do it again, thats what it had orginally, and the two rubber ones you've tried haven't worked out well.

I would still test your oil pressure with an actual test guage.

I would be willing to believe your oil pressure drops low, and I've seen engines run for a long time like that. Actually having zero oil pressure under load for 5 years without showing ill effects is rather unlikely.

 

I dont know if you are doing it or not. But you need a small blob of RTV where the block meets the timing cover and the same thing in the back where the the rear main is

 

I had another truck just like this one, and I replaced the gasket with a rubber gasket, without any silicon, I didn't think it would work with the rubber gasket.
Can I use silicon with rubber and cork gaskets? Do I add silicon between the oil pan and gasket only?

Do I wait 20 minutes for the high temp.? silicon the tack up, before installing oil pan?




93 f150 5.0

 

Put the blob of RTV in the 4 corners then the gasket and pan on. No need to wait

 

Can you use rtv with a rubber gasket?

 

Yes, there is no other way for it to seal in the corners

 

I added black silicon on both sides of oil pan gasket.

 

Sounds like you have some wear in the main bearings. When you apply load, it pushes the crankshaft down against the lower caps. This opens the area at the top where the oil galley is at, thus taking away the restriction which makes your oil pressure go down.

 

thanks for the info. how long can this last, will a large load blow the engine?

 

Can't tell, just drive it easy until you can do something about it.