Leaking Four Speed

Speeder37 · Speeder37's Garage

I have a problem with my transmession leaking to what appears to be the gasket of the attached cover plate.
Can I buy just his gasket?
If I remove this plate, are there any demons that might fall out?
There are four bolts and the small domed shaped indentions
Thanks for your help.

fredmeister · fredmeister's Garage

Mine was weeping there too.
You can buy the gasket sure, and then I recommend installing it with blue silicone gasket sealant to be sure it seals.

The cover is probably slightly warped and its a thin paper gasket that seals there. If anything falls out of there you have problems.

It supports a shift guide bracket that is bolted to the acorn bosses on the inside. Check to see that the nuts holding it are tight before putting the cover back on as above.

Fred
PS: how do you keep that tranny housing so nice and clean.....wow.

Speeder37 · Speeder37's Garage

Does anyone have a part number for that gasket? I see the six bolt gasket, but not the four bolt gasket.
Additionally I'm not clear if removing the cover is going to be a parts falling out challenge.
Reagarding keeping the bottom clean, I am lucky enough to have a lift.
Thanks

JFairman · 08-02-2012, 07:09 PM

Nothings going to fall out other than oil if it's not drained first. I bought a few of those gaskets because it leaked first time I put it back on. Turned out the cover was warped so a thick gasket sealer like silicone doesn't leak.

This is the gasket. Get a few you might need them.
Pelican Parts - Product Information: 915-303-225-00-M260

Speeder37 · Speeder37's Garage

Thanks for the help. I saw that gasket and thought that it was made for six bolts.
I see it properly now

j930 · j930's Garage

the gasket is literally a piece of paper. very delicate so be careful. when i had the tranny redone they sealed it back up with a sealant. i think it was orange. it does not leak any more. the drain plug weeps a bit.

j930 · j930's Garage

when you open it the only thing that will come out is tranny fluid. so you might as well change it while you are in there.

sundevil64 · sundevil64's Garage

Mine is weeping there too! I would think some of the sealants used for a recent top end build should be suitable?

Speeder37 · Speeder37's Garage

I hate to waste the trans oil. I replaced it two weeks ago with Swepco 201. It started leaking right after that.
It doesn't shift as well as it did with whatever oil was in it previously. 1st is stubborn some of the time,
Maybe time to try something different

billjam · billjam's Garage

You don't need a gasket here (or on the other gearbox housing joints). Just get it really clean and use a good quality sealant like Loctite 515 or 518 ... same stuff as used on crankcase and camshaft housings.
I have used this for years on many boxes and never even a weep.

FYI, the inside of the plate looks like this ...

Speeder37 · Speeder37's Garage

Thanks Bill.

Regards

Matt

Matt Monson · 08-03-2012, 08:50 AM

Use Loctite 574 for gearboxes.

Regards,

Matt Monson
Guard Transmission LLC
Guard Transmission |

JFairman · 08-03-2012, 09:11 AM

Just use a gasket there like the factory did. It's only a buck fifty.
Some of those cover plates are warped from the nuts being overtightened and you can see the warp in between the bolt holes when holding a straight edge over the edge of the cover.

I used a thin smear of hylomar gasket sealer on a new paper gasket first time I took that cover off and it leaked a slow drip afterward. That would have worked and Curil T would work just as well there if the cover is not warped and both of these sealents never dry and are easy to clean off with laquer thinner on a rag.

I drained the new Swepco 201 inside and saved it so I could put it back in. I don't want to waste $50 a gallon fresh gear oil either and I poured it through a funnel that has a fine screen filter in the bottom to catch anything that might be in the oil.

I didn't want to buy a new cover or pay a machine shop to machine the edges of the flange flat so I put a thicker than usual bead of silicone gasket sealer on the cover plate in between the bolt holes and with a new paper gasket tried again. This time the oil has never leaked out.

Just want to say I never use silicone gasket sealer on Porsches during usual maintenance or repairs but in this case I had some already and it worked. I waited for the silicone sealer to dry overnight before refilling the gearbox with oil. I didn't want any chance of gearbox oil messing with the silicone as it dried.

billjam · billjam's Garage

I should have mentioned above ... check flatness of the plate before refitting. That is most likely the reason for leaks.
Machining isn't really necessary. Unbolt the steel guide post, remove dowels and rub the plate on a flat surface with wet and dry sandpaper (wet) until you have it flat again. Ten minutes work and a couple of dollars for paper.

There is a whole range of Loctite and other brands of sealant that can be used for engine and gearbox joints, obviously some are better than others, but it shouldn't put a hold on your project if one particular grade isn't available.
518, 574 and others are all specified by Loctite as ... Typically used as a form-in-place gasket on rigid flanged connections, e.g. gearbox and engine casings.

Speeder37 · Speeder37's Garage

Gaskets ordered, sealer purchased,

Thanks for your help gentlemen.

Matt