Oil pan gasket leak

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by jeraldjcook, Nov 28, 2009.

  1. I'm in the process of installing a new clutch and was cleaning off the rear of the engine when I noticed the oil pan gasket leaking. I'll be changing out the rear mail seal as part of the clutch install, but is the oil pan gasket something I need to fix as well or is it fine as it is? Losing a bit of oil doesn't concern me but from what I've read if oil from a leaky rear main seal gets on your clutch it will cause it to start slipping. Since the oil pan gasket is leaking right below the rear mail seal, I have the same concern. It's also leaking all along the driver side of the pan as well.

    Should I fix the oil pan gasket or just let it be?

    Back of engine, leaky gasket mark with green

    Drivers side of oil pan, leaks all along this side too.

    Passenger side of oil pan, no leaks
  2. If you want to change the gasket, its easier to pull the engine and do it than to try to do it with the engine in the car.
  3. 86-93 5.0 Mustang oil pan gasket and oil pump removal & replacement

    Been there, done that - You can do it in the car, but it is hard to do. The best way is to pull the engine.

    Disconnect the battery at the battery ground terminal, remove the fan and fan shroud. Both motor mounts will need to have the large nuts that secure them to the frame removed. The trans mount will also have to be
    loosened, and it is a good idea to remove the drive shaft.

    The rear driveshaft bolts are 12 MM, 12 point, and require a first class box end wrench (ring spanner if you are English or Canadian) to remove them. Don't get cheap here or you will regret it. I set the emergency brake
    and apply a foot to the wrench to loosen the bolts. Notice the paint marks on the driveshaft & rear end flange: align them the same way they came off. If there aren't any marks, get out your paint spray can & make your own marks.
    Have a catch pan in place to get the fluid that comes out of the trans when you pull the driveshaft yoke out.

    I also had to disconnect the cat pipes at the headers to get the engine high enough to remove the oil pan. Be prepared to have to drop the steering rack and disconnect the steering shaft. The flex coupling for the steering shaft needs to be disconnected before you can get the rack out. You should disassemble the coupling by removing the 2 bolts that hold it together. Jack up the engine with a wood block under the oil pan and watch for things that bind or hoses/electrical wiring that may need to be disconnected. I put a couple of wood blocks between the headers and the frame to support the engine. You will likely need to jack up the rear of the transmission as well to get the required clearance.

    Scrape the pan mating surfaces clean as possible - old gasket stuck to the surfaces are a source of leaks.

    Get a high volume/heavy duty pump, and a replacement HD pump shaft. FMS makes one, and ARP does too.
    When you install the pump, the funny looking washer thingy goes on the part of the shaft that fits into the hex socket in the distributor shaft. It keeps the shaft in place when you remove the distributor, which you will have to do to prime the pump. Forget to put it on, and the pump shaft can come loose and fall down in the bottom of the oil pan.

    There is a one piece oil pan gasket which will help re-assembly if you can find it. If you can't get this gasket, use weather strip adhesive to secure the cork gasket to the pan rails and the rubber strips to the bearing caps.
    Use lots of Acetone or MEK to clean the gasket surfaces so the weather strip adhesive will stick good.
    Read the instructions on the adhesive carefully to make sure the gaskets are permanently stuck in place and won't move when you slide the pan in place. Use lots of blue silicone sealer on top of the front and rear rubber seals where they mate with the pan.

    Fill with oil, replace the filter. Reconnect the battery, switch the ignition on to enable the gages, but DON'T crank the car. Remove the distributor and use a 1/4" hex socket to turn the pump counter clockwise
    (same direction as distributor rotation) until you see oil pressure (an external gage is a great help long about now). And keep turning for about 30 sec after you see the pressure come up. A reversible drill is the best tool to use to turn the 1/4" socket. The pressure should come up to about 50-80psi with cold oil. Once you see good pressure, check for obvious leaks, and then and only then, lower everything back into place and bolt down the mounts and anything else you had to take loose.

    Putting the distributor back in is fairly simple. Pull #1 sparkplug, put your finger in the sparkplug hole, crank the engine until you feel compression. Then line up the TDC mark on the balancer with the pointer on the engine block.
    The distributor starts out with the #1 plug wire lined up at about 12:00 with you facing it. Align the rotor to about 11:00, since it will turn clockwise as it slides into place.
    Align the distributor rotor up with the #1 position marked on the cap, slide the distributor down into the block, (you may have to wiggle the rotor slightly to get the gear to engage) and then note where the rotor is pointing.
    If it still lines up with #1 position on the cap, install the clamp and bolt. If not, pull it out and turn 1 tooth forwards or backwards and try again. Put the #1 spark plug back in and tighten it down, put the clamp on the distributor, but don't tighten it too much, as you will have to move the distributor to set the timing. Note that if it doesn't align perfectly with #1 position, you can turn the distributor until it does. The only problem is that if you are too far one way or the other, you can't turn the distributor enough to get the 10-14 degree optimum timing range.

    Set the timing with the engine running using timing light (don't forget to disconnect the SPOUT plug and reconnect it when finished) 12-14 degrees BDC is good. Start up and check for leaks, let it warm up and look again for leaks. It took me 2 days plus, but I am old and slow, maybe your granny is faster.

  4. Wow, what a post. Sorry for taking this bit by bit, but your post raised a number of questions. It sounds like you jacked the engine up high enough to completely remove the pan, correct? The problem I face with jacking up the engine is my mechanical skill level. A/C lines though the fire wall, power steering lines to the steering rack, and other lines that frankly I have no idea what they do all present obstacles (for me at least) to raising the engine. It looks like I could drop the oil pan maybe 2-3 inches before it would hit the k-member. Any chance I could just drop the pan that far and swap out the gaskets?

    Good to know, and I suppose this would be of particular difficulty if I tried to do it my proposed method. The current gasket is definitely NOT cork. It seem to almost be rubber and looks like it would be easier to remove but who knows.

    The 3 year plan for this car is a 347 stroker so this upgrade will probably have to wait until then.

    I hope this part was only if I installed a new oil pump. Messing with the distributor, setting the time, etc, is a lesson I hoping to save for another day.

    Thanks for you very detailed post. :hail2:
  5. Sorry 5.0Droptop I missed your post. Thanks for your input. Looks like pulling the engine might be the only practical solution.
  6. If you have air tools changing the oil pan gasket is a sinch. The major part is lifting the motor. You can lift the motor with a jack and put 2 small 2x4's in between the mounts and the chassis to get clearance. With an air ratchet and extensions you can get the all the bolts in 10 mins. Make sure to get the one piece gasket set. It makes life so much easier, especially the plastic pins that hold the pan up.

    I just put these piece of wood in between the mounts and k-member and this gave me enough room to lower the pan and change the gasket no problem. You cant actually take the pan out though unless you remove the rack and pinon.

  7. I agree that the best way is to pull the engine and reseal. It's a PITA to do it in the car, unless you want to drop the K-member.

    One thing I would consider is why it's leaking. Check the function of the PCV system, make sure the valve is working and the screen is clear, might as well just replace it. Another thing to consider is if you are getting excessive blowby your piston rings which is causing excessive pressure. In that case you might need to rebuild. Of course you can still just reseal but six months later all your efforts are going to seem wasted as you will probally start seeing leaks again.
  8. If this is the plan I wouldnt mess with the pan gasket. You might try tightening the pan bolts to help slow any leaks.
  9. OK, I did the AOD to T5 swap, and during the process, was keeping an eye out on whether my oil leak was caused by rear main or oil pan gasket. Well it didn't take long to find out, once I had the transmission off, the oil pan gasket was blown to bits in the rear, and had multiple places where it was blown out on the sides and front.

    Well, I said screw it, there's no way I'm getting the engine up 4". Most likely my wife would find me in the garage crushed by the engine block.

    So I buttoned up the flywheel, clutch, etc and finished up my T5 swap, then took the car to a good mechanic. He changed out the pan gasket for $250. :flag:

    edit: 1 piece felpro is the way to go, also I got the car like this from previous owner running a supercharger. I checked some lines and a line that goes from intake to this thing that plugs into the charcoal canister might have worked it's way loose, so I plugged it back in.

    yours doesn't look that bad at all.
  10. When i put on a timing cover gasket about a yr and a half ago, I cant remember rather I put silicone under the metal gasket or not. Today when I was cleaning the front of the pan where the TC meets, I noticed a gray silicone gasket formed the shape of the metal gasket and was wondering rather that is a factory silicone gasket that needs to just be cut and more permatex put under as well as on top or just leave that one under there? I would think to juust cut it and put a fresh bead under but just asking to make sure sure

    Mine is a 95 by the way oil pan front gasket seal permatex.jpg
  11. So I've done the the oil pump swap while the engine is in the car. Problems of A/C line clearance will appear, had to break the system open to lift the engine higher. Which I later swapped to r134, so it needed it anyways.
  12. any thoughts on my question?
  13. I would scrape away any old silicone or rtv you see. A small amount smeared on the old gasket would probably aid in sealing.

  14. I personally would get old off and add new on, if I'm there I'd rather know I got it sealed up good for sure than wonder will it hold, that's just me.
  15. yeah i guess i can cut that old one under the metal gasket off and just put a good bead under the metal gasket and it should be fine right?
  16. It's hard to tell in your picture exactly what you have. However, I have the blue felpro one piece gasket. When I swapped cams, the end seal tore off leaving just the rubber and metal reinforced part. A lot of the rubber had come off the gasket and the metal was showing through. I cleaned it up a little and put a thin film of rtv on. Two years and no problems.

  17. yeah im not sure if the metal piece was suppose to stay in tack with the pan or not but with mine the metal part is definitely sticking up and i can see the rubber under it. I'm thinking if i cut that piece off under the metal and just bead up a layer of silicone on both sides under the bottom as well as the top, it should be all good.

    did u put rtv on the underside of the metal gasket as well?
  18. I prefer the blue Felpro one piece gasket. It's expensive, but I have never had one leak. You put it on dry.

  19. well im not going to pull the motor yet so not going to change the whole gasket.

    Kurt what did u think about what i said about putting that ptfe sealant on all the water pump and thermotat bolts as well?
  20. Anywhere a bolt goes through to the water jacket, put PTFE on it. So that goes for water pump bolts and thermostat outlet bolts as well.