Pre-war (up to 1942) 1939 LaSalle Oil Leak and Drive Shaft Mystery

[39LaSalleDriver]

Oh, the things you find when you go digging around...

Back in April, I had the rear main seal replaced and gave instructions to the shop to clean the oil pan/pump/etc. up. Presumably they did all this, yet I still had an oil leak. Part of it I could tell was coming from the oil pan drain plug, and so I resolved to put one of those drain plug washers on there (since the shop did not) with my next oil change to see if that cured the problem.

This week, I resolved to go ahead and change the oil since it was looking pretty nasty on my dipstick and also look into the steering box and differential as well since I have no idea when (or if) they were ever tended to. Changed the oil, put a washer on, and that seems to have fixed that drip. However, I am still finding spotting on my driveway. It seems to be coming from a cover that goes around the junction where the engine and transmission meet. More specifically, there seems to be a drain? or weep? hole in the bottom of that cover (see photo). Oil might be coming from that since I am finding droplets in that area, or they could be coming from the back edge of the oil pan, and down the face of that cover. I have yet to determine which. What is that cover, and should there be oil dripping from it?

This car also has a LOT of caked on oil, grease, and dirt on the underside from the oil pan to the drive shaft. When it cools off outside I am going to try and get under there with a household steam cleaner and get as much of that out of there as I can. For now I've hit quite a bit of it with a putty knife and it was then that I got to looking at my drive shaft really close.

On the transmission end, from the U joint to the drive shaft I have about 3/4" of exposed roller bearings  Surely this isn't normal is it? Closer examination shows me there is a grease zerk on the drive shaft itself (which I don't think is supposed to be there), and what appears to be a weld line about 5" back from the U joint. Does anyone have any thoughts about what's going on here? I'm wondering if someone long before me has put a drive shaft on there that was too short, and somehow welded an extension onto it. So far as I can tell, other than slinging grease all over the underside of the car it hasn't posed a problem. But I'm not wild about exposed bearings. Any suggestions as to what I should do...source a new drive shaft? leave well enough alone? rig some way to cover the bearings? Thanks

[Steve Passmore]

Let's try and cover this one point at a time Jon.
1.  There is no conventional seal to the rear of the engine only two half round strips that sit tightly in a grove.
There are those that advocate replacing these seals while the crankshaft is still in the car but I have never found this to be successful'   It's likely the garaged tried to do it this way and it's failed. (if they did it at all?) These seals have to be pressed in with a special tool and the crank is in the way for this procedure but let's assume they did it this way.
They would have to remove the oil pan and transmission at least. They surely would not have replaced the old oil and a new pan gasket is a must so whats going on here.

2,  The cover you speak of is the clutch pan, there to keep muck off the clutch and the hole to drain any oil getting past the rear main seal, like yours.

3, What your looking at on the drive shaft is not a bearing, its the spines of your slip joint with the cover slipped off exposing them. The cover is towards the front buried in crud. You will need to dig it free.   When the splines are covered the zirk is to get grease into the splines necessary for rear suspension movement when the drive shaft changes length on bumps.

I would look very closely at what this shop charged you for and what they actually did.  Seems to me they did nothing!

[Dan LeBlanc]

Maybe this will work

[39LaSalleDriver]

Steve to the rescue! Thanks guys. 

Let's try and cover this one point at a time Jon.
1.  There is no conventional seal to the rear of the engine only two half round strips that sit tightly in a grove.
There are those that advocate replacing these seals while the crankshaft is still in the car but I have never found this to be successful'   It's likely the garaged tried to do it this way and it's failed. (if they did it at all?) These seals have to be pressed in with a special tool and the crank is in the way for this procedure but let's assume they did it this way.
They would have to remove the oil pan and transmission at least. They surely would not have replaced the old oil and a new pan gasket is a must so whats going on here...I would look very closely at what this shop charged you for and what they actually did.  Seems to me they did nothing!

Since I provided the instructions to the shop on how to replace the rear main seal (with info from this forum) as they had no experience with pre-war cars (mainly 50s and 60s hot rod type stuff), your assumption is correct that they just dropped the pan and lowered the crank slightly to reinstall. They guy did indicate that afterwards it was still dripping a bit, just not as much. Can't say that I'm happy about it, but I can live with it I suppose. It is absolutely maddening because I can't for sure verify if they actually did the work! I at least know they had the oil pan out and removed the sludge though. We won't get into how much they charged for doing this and replacing the entire brake system with me providing all new parts at the same time. Not to mention that it was supposed to be done in about four days, and took over three weeks...labor charges that I had to eat because of their poor work practices. As far as I can tell, it was largely because they couldn't figure out how to get the hubs off and sat around running the clock while figuring out what to do! When they finally confessed to what the hold up was, and that they were going to have to order a "special tool" I said "What? A hub puller? I've got one at the house." Let's just say I won't be going back to that garage. 

2,  The cover you speak of is the clutch pan, there to keep muck off the clutch and the hole to drain any oil getting past the rear main seal, like yours.

Excellent! Good to know. This then is likely the source of my drip.

3, What your looking at on the drive shaft is not a bearing, its the spines of your slip joint with the cover slipped off exposing them. The cover is towards the front buried in crud. You will need to dig it free.   When the splines are covered the zirk is to get grease into the splines necessary for rear suspension movement when the drive shaft changes length on bumps.

So as I am reading this, I get the idea that the drive shaft is in effect floating between the U joints? Everything seems tight and I cannot detect any slop when I try to move it by hand. I do see the "cup" type of cover you mention. So I take it that it looks like I have the right parts, but I should get that slipped backwards to cover the splines? I had planned on replacing the U joints with ones that hopefully have zerk fittings this fall anyway so I may just wait a month or two and drop the whole shaft and clean it all up when I replace those. Does that sound like a reasonable plan or should I be more concerned right now? I have no earthly idea how long it's been this way, but from the looks of the grease buildup on the underside of the car, I'd say for quite a while.

[Steve Passmore]

I would at least try to get the cover back over the splines to stop any more crud getting in there.

[39LaSalleDriver]

Will do. Thanks Steve.