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Oil Pan Gasket - 1 piece- leaks, suggestions

904Bronco

Contributor
Bronco Guru
Joined
Sep 28, 2004
Messages
5,749
Loc.
San Martin, CA
Pan Leaks front and back...
So I have a rebuilt 1990 Mustang motor that I changed out the 77 Factory oil pan (imagine large quantities of silicon sealer that still leaked) and put on a brand new 97 Explorer stamped steel oil pan. Put it together on the engine stand, before it went in the rig. I used the one piece Fel-pro blue silicon seal pan gasket. After 1000 miles it started leaking at the ends. I dropped the pan in the rig, cleaned everything up, and put it together with another new 1 piece silicon oil pan gasket. I used just the smallest amount of silicon sealer in the coners of the gasket front and back. It is still leaking ?:? I have confirmed the gasket as the correct one, right pan bolts and pan stiffener rails on the pan. I have the same set up on my 75 and there has never been a leak. ?:? I am looking for suggestions for when I drop it again. I have asked around locally and been told to "use more silicon sealer" up to "I should use none" I hate f*#king leaks... :mad:
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
Crankcase ventalation? Are you vented well enough to prevent excess presure from pushing the seal out?
 
OP
OP
904Bronco

904Bronco

Contributor
Bronco Guru
Joined
Sep 28, 2004
Messages
5,749
Loc.
San Martin, CA
Crankcase ventalation? Are you vented well enough to prevent excess presure from pushing the seal out?

I looked at that, it is the right PCV, supply tube clear, as is carb spacer, vacuum to it and it is sucking. Air cleaner open on the inlet side, no blockage.
 

RnrdTheFox

Sr. Member
Joined
Dec 4, 2005
Messages
727
Loc.
Superior, CO
I had the same issue when I replaced my old engine with the 97 Explorer engine. I noticed '97 was leaking previously at the rear so I figured the smart thing would be to replace it with a new one. Replaced it and fired it up the first time and it leaked almost like you were pouring oil on the ground from the front. Dropped the pan and tried again. This time it leaked worse, except from the back. Got pissed off, bought another new gasket and tried again.

This time I did it as follows.

1. Clean out all of the old silicone at the corners. Dig it out with a pick or whatever you have to use.
2. Use a liberal amount of silicone at the corners. (The factory gasket only had silicon at the corners.)
3. Without putting on the pan, use the four bolts and washers to position the gasket at the proper location at each corner and allow to dry.
4. Apply a thin amount of silicone on the other sealing surface
5. Position the pan and keep everything aligned, hand tightent the four end bolts.
6. Loosely tighten the end bolts and hand tighten the rest of the pan bolts.
7. Snug down the ends, then work your way aroud the pan and tighten to spec.

Unconventional I know, but it worked. I don't look forward to the next time I have to change it. So far, no leaks. Hope this helps.
 

bronco italiano

Contributor
Bronco Guru
Joined
Feb 1, 2004
Messages
1,954
904 did you also change the rear main seal? I use the threadlocker sealant on all my bolt's but to do a pan still in a bronco and not upside down is real hard as you always get some oil drip down the block wall. I usually after a gasket change let the vehicle sit for 24 hours before adding any fluid. They are just tough. Is the pan "tweaked " in any way? Good luck and let us know. BI
 
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