Packard Forum Index » Post-War (1946-54)

I bought a 51 Packard 200 Deluxe and have replaced the fuel tank and pump to get it to run. Then adjusted the carburetor (still in pretty good shape) to get it to idle smooth. After I did this I noticed that there was an oil leak from the bottom somewhere. When I bought the car I found an oil pan gasket set in the trunk. When I replaced the fuel pump I found that the someone had put the fuel pump gasket on upside down-no gasket mating surface on the top 1/3 of the pump to engine. I was hoping that after I replaced it correctly that would solve the problem. It did solve that leak. The leak that remains is coming from the lower clutch pan drain hole. That is what I didn't want to see. I have never done a rear main seal on a flat head Packard-or any flat head engine for that matter. I have done many on V-8s & 6s. Are these the 2 part rope seal that can be accessed by dropping the oil pan? If I have to pull the tranny I may as well do a clutch set as well, although the clutch seems to be good so far.

It is the two part rope seal although some have managed to install a modern neoprene seal. You might search the forum for threads on other rear main oil leaks to see which models it was done on and the seal used. If the car has an Ultramatic the front seal around the converter pump shaft could have been dry or cracked and could also be the source of the leak.

So, I noticed that the crankshaft oil seal diameter is the same for the 288/327/359 Packards and the many varieties of Chrysler that used the same seal as the Chrysler 440 and Slant Six, which was originally a rope seal.

Someone on this forum said that the varieties of modern neoprene seal worked, but the mechanic said that he had to make a shim for it.

I am just getting ready to put the crankshaft in along with a new rear main seal on my 1953 327. I have a new Graph-Tite rope seal that came in the kit from Kanter. I also went and bought a FEL-BS40240, which is the modern neoprene replacement for the rope seal. I have looked at it quite a bit and cannot really ascertain where the shim might be needed. But if I was going to try to do this with the engine still in the car, maybe I would think about the Neoprene seals.

Here is a nice video about how to take off the oil pan:

youtube.com/watch?v=8uyrBl3oq0I" rel="noopener external" title="">Oil Pan Removal 1947

This thread is useful as well:

Rear Main Seal 356

This is the Best Gasket Rope Seal for the Packard:

Look for 5470S


This is the Best Gasket Rope Seal for the Chrysler Slant 6/440

Look for 5297

This is the Best Gasket Neoprene Seal for the Chrysler Slant 6/440

Look for 3879E

A nice source forthese:

marxparts.com/Rear%20Main%20Seals.htm

Thanks Howard and Jerome. I have done these before and I agree with everyone that said it is NOT A FUN JOB! I read in the Motor Repair manual that I will need to hook up a hoist to the engine to lift slightly, but won't need to take bolts out of motor mounts. Anyone do this? I tired to look up the utube video but it was gone.

You may have to lift the engine slightly to get a wrench on the bolts holding the pan. A few are directly over the front crossmember and then you will need enough room to slide the pan out.

On some models the steering idler may need to unbolt off the right side frame rail and move out of the way so the pan can drop down. The crank may also need to turn after you start sliding the pan so as to move the counterweights so they don't interfere.

Be careful of how much you try to lift if the mounts stay bolted. The vulcanized rubber on the 70 year old mounts is most likely dry and hard as a rock so could separate from mount metal pieces on one side or the other. if you can keep the engine attached to the lift for support it may be prudent to unbolt the motor mounts from the frame before and during the lift.

That's what I was thinking Howard. I have never lifted an engine for clearance and left the mounting bolts intact.

Here's another good project blog about this:

Project Blog Page 38, 1953 Clipper Rear Main Seal

On my 1953 327 I could get the oil pan off by dropping the right idler arm and then was able to get the wrench in to the oil pan bolts under the frame crossmember through the access holes. I didn't need to raise the engine. However, it took a long time because there was not a lot of room to turn the wrench, so it was very tedious.

One other thing I noticed:

Max Merrit has a "new style rear main seal + stick kit, better sealing capacity" listed for $35.00

362010K-NS

Max Merritt new style rear main seal + stick kit for 1948-1954

Wonder what that is?

One of my old mechanic friends stopped by this Morning. I showed him my projects. He was particularly interested in the Packard. I told him about the rear seal leak and he took a look. He used to work on these a lot and has rebuilt the exact engine that is in my Packard. He then asked me how long it has been sitting. I told him that I wasn't sure but probably at least a year or two. He told me that the rear seals in these are made of jute or hemp, I forget which he said, and graphite. He thought that if I would run it off and on for a month or so, the seal may absorb the oil and start to expand and seal again. Come to think of it, when I went through the trunk there were some newer 10w-30 empty oil bottles. I use Brad Penn 30w in my classics. I will do an oil and filter change, then do like Glenn said and run the engine off, with a catch pan under the engine off and on for a month and see what happens.