BrianG

Does anyone out there have a servicable oil pan for my '86.5 4-sp automatic transmission? The best price from any of the Big 3 is almost $500.00 US.

Now, I don't mind paying for the thing if it's the actual cause of the leaking, but the new part has to come from Germany, so it is not returnable if it's not the issue. So, I'd like to try a known-good part to test the assumption that it is the culprit.

I have worked to reduce the possibilities by replacing the cooler-lines and the reservoir and the shifter-shaft seal. Looking up into the front end of the tranny-housing reveals a clean-and-dry torque converter. So, the probabilities take us to where the source seems to be down to the pan.

This actually makes sense since the leak started right after I took the car in for "spring service" to the local "Porsche expert". With a torque spec of 75 in/lb I'd bet they over-torqued the thing and twisted it, but of course........... "we didn't do anything wrong!"

Anyway, I'd appreciate the assistance in finalizing the need for this investment by trial-fitting a known-good one first.

Thanks!

BrianG

Jim_H

I did this before, don't remeber 75lbs being the torque value, seems high? Off to the manuals I go.

BrianG

Jim............. note INCH - lbs

NOT ft-lbs!!

Jim_H

You didn't mean 75lbs? The pan gasket is a very thick rubber one. Maybe you meant 7.5lbs? I can never find torque values in the manuals but I would guess they would snap @ 75. As I remember I just snugged them.

Jim_H

OK, yep, got it


nevermind

jpitman2

I had a couple of tries getting the feed pipe to pan washers to seal....on a 3 speed though - same set up from the reservoir?
jp 83 Euro S AT 48k

Garth S

Brian,
I presume you've already removed the pan to check the gasket for cuts, pinches, or misplacement - and also have run a straight edge around the pan sealing surfaces: and everything is OK?
I just took a look at the S4, and the pan is very robust - next to impossible to warp drawing up to a machined housing with 6 - 6mm bolts: the only potential I saw was if one of the pan locating tabs was bent inward, it could jam against the case preventing the gasket being properly compressed.
In the worst case, for 'lesser' cars, xmission shops are known to run a bead of the appropriate sealant between the pan and gasket: there is some superior auto Xmission knowledge here with a select few - and I would seek their blessing on that issue before acting : but I can get the name of the sealant if req'd.

John Struthers

The trouble with that sealant is that some perfectionist might try to clean it off ...right down to the sealing faces -and beyond-. So while the surfaces may look bright and shiny, even square with a straight edge there can be a 'nick' that will leak when cool, seal when running -heat expansion- then leak again at/during/after cooldown.
Conversely, if the sealant dried 'HARD' and was not completely removed a mini bump will cause a leak during the same heat-up and cooldown.
I know you don't want to hear this but most likely the guru's, Steve C. in particular, will probably advise you of a seal leak with an eye toward either the TC drain plug or the tranny seal (forward).
If you can't reach this without major dissassembly and the leak isn't severe just keep an eye on fluid level and keep on trucking.
Yeah, I'm with you on trying to find and fix all leaks but if it's not putting a 8 inch puddle down - overnight - after a brisk run don't sweat it.
There comes a time when the effort is not worth the result, even if it stops the leak.
Lemme see...
Raise the sHARk, drop the exhaust, pull the heat shields, pull TT, disconnect all manner of electrical, cooling, brake lines, possibly loosen remove suspension, short aka half-shafts , CV's drop tranny, pull TC and replace a seal that cost's less than $10.00, plus all the work and replacement stuff you'll do (TRUST ME!) while you are in there. All for a weep or minor leak???? Don't do it, at least not now. This is a fairly involved winter project that you can plan and $$$Save$$$ for starting now.
In the meantime enjoy your sHARk, buy the WSM's, a good digital camera a small mound of freezer/lunch ziplocksreview all sites and links for the repair -didn't Tony'vegas babyyy' do this on film? if not do your own camera teardown and have a notebook handy because you won't believe how much you can forget after even a minor delay due to parts, work, family business. Getting a handle on tool needs is a good idea, too. You can hit pawn shops and swap meets/estate sales and make a killing.
Purist/nit-picker flame-deflector:
We seek perfection seldom is perfection attained.
Besides, a little parts/brake cleaner and the pressure wand at the House of Sud's should keep you clean oil leak and all....at least for a little while!

mpesik

Hi there Mr.Brian G. Can you tell exactly where the leak is localized coming from the pan? What length does this leak appear to be? Mike.

BrianG

I read you John. With what I've done so far, you'd think i'd be close, but the leak is substantial. After an hour of driving, the undercarriage is pretty much soaked, including the exhaust bits. You can imagine how nice that is! It will drip like a leaky faucet for about 10 minutes and leave a stain of perhaps 2 ft diameter, over-night.

I agree that the pan is pretty substantial and looks difficult to tweak, but on the hoist, with the engine running, you can actually see the fluid slowly seeping along the gasket line in the vicinity of the reservoir. There does not seem to be another source in that area for a trickle-down leak. I've checked the TV-cable seal and the shift-shaft seal, and the vac-modulator seal, and the front pump seal.......... all clean and dry up there.

I have half a mind to grind off the "stand-off tabs" a couple of mm and see if that helps.

Brendan has a pan that I'm going to try. That ought to answer this question.............

mpesik

Hi Brian G. Maybe try this. Get some clear ,thin flexable tubing,the kind that's used for aquarium air pumps.Cut it lengthwise,but only one side. Surround the whole circumferance of the pan lip with it. Make sure the ends butt up against each other. Then add a little silicone to the ends so there is no gap. Put your rubber gasket on top and replace .Bet you 5bucks it'll work. That's canadian dollars!! Note the thinner the tubing the better. goodluck. Mike.

BrianG

Hey, it's worth a try, with $600.00 Canadian Peso's at risk. I see the theory of your proposal and it makes sense. I'll give it a whirl.

Thanks!

928FIXER

Did you use a "factory" porsche part or a aftermarket supplied part???I have had a lot of problems with the aftermarket pan gasket sealing on both my 928 and M-B 300 which use the same gasket.I now always buy the gasket form the Benz dealer whenever I'm doing a trans servive on either vehicle.
Is that $500 for a new or used pan???If its for a used one I've got a couple of dead 4 speed autos around that I would be more then willing to sell the pan off of!

BrianG

That's $500 for a new pan, and the Big 3 don't seem to have any used ones that they'd part with. I guess they aren't interested in parting out a decent tranny.
I got the gasket from the Porsche dealer but didn't see a Porsche or MB logo on anything.
If you can fwd the ident infor on your MB 300 I could try the MB dealer.

Thanks.

Steve Cattaneo

In all my years of rebuilding Mercedes Benz transmissions and I have done hundreds, I have never seen a twisted pan. Since the pan was removed, the most likely cause of the leak is the rubber gasket; it is probably out of position on the pan; remove the pan and center the gasket. Toque the bolts to 71 in.lbs. Also clean the oil reservoir. This type of pan was not design for any GLUE.