Frustrating Oil Leak

[BILLF/TRF]

I came home last night after a 120 mile cruise and noticed oil drops all the way up the driveway, a little puddle in front of the garage door and then two puddles of about 4-5 inches across on the garage floor after the car sat for awhile. The drippings are basically from the little hole at the back of the oil pan but tend to drip off any low point at the rear oil pan (59AB engine). I have twice re-done the rear main seal and can't believe its leaking again--if it is the seal? I am wondering what else to do and if I should pull the engine and look again or just drive the rest of the summer and keep an eye on the oil level (it was down about 1/16 inch on the dip stick after the trip). Thanks for any suggestions.

[Vic Piano]

Welcome to the wonderful world of Flathead Fords... Most of them leaked at the factory before there was any oil in them... Seriously, I've never had a Flathead that didn't leak a little after getting some miles on it. I wouldn't worry about, just drive it and keep an eye on the oil level... Have fun with it.

[jdl]

Iv'e been told if you keep the oil level 1/2 qt low it won't leak as much. ???

[Steves46]

As Vic already mentioned, oil leaks and Flatheads go together like bacon & eggs. Now I know why most driveways in the early days were two paved strips for the wheels with dead grass in the center. Just periodically check your oil and enjoy.

[Brendan]

yeah, don't they all leak. mine leaks like a sieve

[harry goebel]

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I recently pulled the pan and installed the best gasket and new rear seal. I followed instructions about letting the rear seal protrude a little. I then called the Best Tech and inquired if I should leave the gasket hole or stop at the rear seal. He said it did not make any difference one way or another. Believe me it does make a difference and I have the oil leak to prove it. I left the gasket hole and covered the area of the rear seal, big mistake, should have cut off and let the gasket but up against the rear seal. I think I will let it leak.

[SigmaRho1416]

Just remember, If there is no oil under it there is no oil in it!!!

[Lawson Cox]

Don't worry about that oil leak. It is just marking its territory. Drive the heck out of it. Enjoy

[ford1]

there are only a few places for the oil to leak out the back of the engine, oil pan pan casket, main seal, or out the gasket at the back of the engine where the rear cam bearing gasket and plate bolts onto the rear of the engine

[Karl Wolf]

I remember that at the side of the rear main there was a gap between the rear main bearing cap and the block... Machined that way... This would be next to where the pan gasket ends. I might have put a bit of silicone in between the cap and the block and just touching the pan gasket ends... My 59ab does not leak a drop... Karl

[flatjack9]

Another place to check is your oil pressure sender. They will leak down the back of the block and look like a seal is leaking. Also is your breather cap clean? If it is not, it can cause a pressure build up in the engine and force oil out.

[Flathead Fever]

You need to go on the Pasadena Roadster Reliability Run. After all those flathead powered roadsters leave the parking lot it makes the recent Gulf Coast oil drilling disaster look insignificant in comparison.

Obviously, if your flathead wasn't leaking before and its leaking now it not because its a flathead, there is something wrong. Its' going to leak a little out the rear main seal but not as bad as your describing. Did you ever notice the cotter pin from the factory that is installed in a hole at the rear of the oil pan below the clutch bell housing. My guess is that it was designed to keep the hole from plugging up so your clutch bell housing would not fill up with oil. A little seepage was normal back when they were making gaskets out of rope and tree bark.

You could try having British Petroleum lower a tube down to the rear main seal and pack the hole with mud and concrete.

Jerry

[Kahuna]

I would also want to know how much oil you are putting into the engine? If no filter, then 4 quarts is correct. If you have a regular sized cannister filter, the 5 quarts.
Jim

[1938 Woody Cape Cod]

The same thingn happened to me, my 35 used 2 qts on a 100 mile trip. [had just changed the oil ] same deal a trail into the garage, the next day I brought it up to the full mark and I've only had normal leakage since. still a mystery..............Bob

[Bassman/NZ]

I would suggest the rear main bearing shell is getting a bit worn, causing the new seal to go out of round a little.
What we used to do in the old days when flatheads were so cheap and readily available that we never rebuilt them, just replaced them, was to make up a little contraption out of a tin lid or any suitable metal container bolted to a piece of strap steel which was in turn attached to a bellhousing or oilpan bolt. This caught all the drips, and once a week, month or whatever we'd drain it and re-install. We used a wingnut so it could be detached and drained in a matter of seconds.

[DD931]

I agree with the notion that "...if it ain't leaking it's empty..." but flatjack9 makes a good recommendation about checking your oil pressure sender - I wouldn't think so if it hadn't happened to me!! I didn't realize it was leaking until my brother, who was following me, mentioned it. I parked and watched a pool collect. I had been on the road long enough to have lost at least a quart!! Sounds like too much leakage (drips coming up the driveway) for the usual rear seal leak - particularly if it hadn't been doing this before. They don't usually develop a big leak all of a sudden!

Norm

[52merc]

do you have the cover that goes on the housing that covers the starter if this is missing you can get a oil leak from rear main

[flatjack9]

Originally Posted by 52merc

do you have the cover that goes on the housing that covers the starter if this is missing you can get a oil leak from rear main

Would you explain that?

[FlatheadTed]

Be aware of the front oil can blow back if the gasket is not on the Dizy and pulley seal is of

[BILLF/TRF]

I want to thank all of you who have responded. I have checked out a few things that were mentioned. I don't have an oil filter and fill it with 3 1/2 to 4 quarts of oil (10W30) at oil change time. I have ruled out the leaky oil pressure sending unit and oil fill cap--there was no evidence of oil trails from the oil unit and the oil cap is new and clean. I like the idea of using some silicone in areas of concern (around seals and gaskets). I remember using it extensively on my Model A engine oil leak and it really helped. Still baffling is the continuation of dripping- not much, but even a day later! As far as the dripping up the driveway, one explanation is that I live in very flat country and when going up on the inclined driveway, any collected oil in the flywheel housing may have dripped out at that time. The two puddles are directly under the little hole w/cotterpin in the back section of the oil pan (flywheel housing) and from under (?) the left front corner of the flywheel housing where it attaches to the oil pan proper. The last time I had the engine out of the car I looked for holes in the oil pan but did not see any. So for now I will just enjoy the car, check the oil level regularly and be sure not to park on someones new concrete driveway! Thanks, Bill