I have a 1990 f-150 with the 351 windsor engine in it, and have recently been experiencing an increasingly bothersome oil leak from the bottom of the engine. it appears that the oil pan gasket has been squeezed out of position, and oil is running out at the back of the pan. this happens when it has been running and stops dripping soon after the engine stops, i assume from the oil settling back into the pan. I tightened the pan some, and the leak slowed, but it's still getting crap all over the bottom of the truck. has anyone else had this problem? I know ill have to jack up the engine to remove the pan to replace the gasket (Chiltons says to remove the transmission crossmember, too! is this necessary?). i was hoping i could get some pointers/advice/shortcuts on this matter, and if there is some way to prevent it from happening again. TIA (very much)

chuck

 

I have a 1989 f-150 with a 302 and I had the same problem. I replaced the pan gasket and it fixed it. I know the job is probably a little different on the 302 than it is on the 351 but it was a big job. It took me almost two days to fix my truck. I had to remove the exhaust system, radiator, starter, upper intake manifold, drive shaft, and transmissions cross-member. I had to take the nuts off the motor mounts, do some creative jacking with a few floor jacks on the motor and transmission. The most difficult thing I had to do, which I don’t know if it the same on the 351, is to drop the pan down on a frame piece and work in a tight space between the pan and motor to take the oil pump off and let it drop in the pan before the pan would come completely off. Installation of the pump was even worse, I had to put the pump in the pan, slide the pan into place and put the pump back on. It was also a pain getting the motor, transmission, and exhaust system to all line up properly once everything is lowered back into place, it too more creative jacking, a come along, and a big metal pipe to push it around. The new pan gasket was in my opinion, much better than what was on there before. It was one-piece rubber with metal rings where the bolt holes are. I got the gasket from Napa.

 

On my '82 351 w/carb; I simply removed the nuts from the tranny mount and motor mounts; used an engine hoist to raise everything about 4"; placed a 4X4 between the motor mount on the frame and the motor mount on the engine; dropped and removed the oil pan; replaced the gasket; reversed the operation. Mine was brand new and I had to change the oil pan (the front sump pan did not work!) and oil pickup and put it back together.

Definitely go with the one piece rubber gasket with the steel inserts. They work really well and keep you from crushing the gasket. I put a thin layer of black rtv on the block; let it sit to get tacky; put the gasket on and held it in place (sometimes requires 4 hands) until it stayed in place by itself; then replaced the pan. The one piece gasket is real nice for going around the front and rear seals.

Good luck,

Slik

 

thanks for your experiences. chiltons says it is similar to the '89 302, I think they even use the same instruction list, but i think the upper intake, etc. has to be removed just so it doesn't contact the hood while it's closed, so i might be able to leave the hood open & skip a few steps.. maybe.

thanks again
chuck

 

On the 302 the upper intake manifold is removed because when the motor is jacked up to do the repair it will hit the top of the truck behind the hood. Can't say for the 351 though. And I forgot that I had to have some short 2x4's to support the motor after it's jacked up. As a side note you may want to see if your rear main seal can be replaced from under the truck while you have the pan off, here again, can't say with the 351. Happy wrench turning!

 

I changed my oil pan gasket on my 90 F-150 302 without raising the engine at all. The hardest part was getting the bolts out, but with a few different extensions on the ratchet it can be done. It had a one piece gasket on it, which came right off, and i replaced it with a cork and rubber set. The job took two doing it like this, but that was mostly because it was middle of winter and I have no heat in the shop.j