1993 505 GTI wagon – How to stop the ATF leaks?

[Hugo]

Hi all


I have a 1993 505 GTI wagon.


The 4HP22 automatic transmission is leaking AFT. It has not been serviced for a long time. I have just recently removed it and it looks like this:








I have already replaced the filter and the sump gasket, but it was still leaking a lot, for instance:






I’m currently thinking of stopping the worst leaks now and at some time in the future having the transmission professionally rebuilt.


Has anyone been here before that has any tips about how to stop the worst leaks?



Thanks,
Hugo

 

[Pug72]

My ZF3HP12 in my 504 was leaking like a sieve from the selector shaft, pan gasket, rear seal and the dipstick tube. I sourced a gasket kit from Cobra Transmission in the US. No more leaks! I can no longer buy the stainless steel filter for mine, but they can be washed out and reused thankfully.

 

[Codman]

I had mine fully built for the turbo by Dave at Torque shift, he is familiar with them from BMW and Jeeps, and an honest fellow to deal with if you get stuck

 

[Beano]

I can't say anything about the 4 speed, though it is similar in some ways to the 3 speed.
My 3 speed had no leaks.
It would have been better to degrease it when it was still in the car and then get uder at night with a torch and see where each individual leak came from, but don't feel bad about not having done that.
It's just the usual suspects :

Buy some new flexible hose and put two hose clamps on each end.
With only 4 bolts on the 3-speed and 6 on the 4-speed, , those sumps look like they're likely to leak but are usually good. Just pay attention to how much tension you put on each, and how much the clips splay out when you tighten them.

You may like to put a very thin smear of the "permanently sticky" Permatex gasket goo on the connection where the dipstick tube comes out. But never use silicone.....auto gearboxes do not like contamiunation at all....there are multitudinous tine channels in them which can get clogged up easily.

New front and rear oil seals, naturally.
New O-ring for the speedo drive.

And just pay attention to each place you think it may leak. Don't employ the "that's good enough" mentality...

 

[4cvg]

source & fit manual transmission?

 

[Hugo]

Hi everyone,

Thanks for all your suggestions.

I have cleaned the outside now and placed the transmission on an engine stand. After thinking about it a bit more, it is clear where the leaks might come from, primarily:
Front and rear seals
Selector lever
Cooler pipe unions
Dipstick pipe
Kick down cable
Inhibitor switch
Breather
Speedo drive


I will refill it with ATF and test it for leaks (as best I can) to confirm my suspicions. Before, since it was so dirty, it was harder to trace leaks. I will then replace as many of the items above as I can and test it again for leaks.

@Pug72, thanks for those tips.

@Codman, Thanks for that tip. My strategy for the moment is to get the car back together again and at some point in the future get the transmission rebuilt. I have a transmission place in the north of Melbourne in mind.

@speaksgeek, I’m not normally an optimist, but I think it is most likely possible to stop the leaks, especially if you can identify where they are coming from. Time will tell. I’ll post updates back here to let you know how it goes.

@Beano, it was SO dirty, I really wanted to remove it and clean it. Having it on a stand certainly made cleaning easier and will hopefully help make certain tasks like fitting the kick down cable easier. Thanks very much for the other tips.

@4cvg, thanks for the idea, but although this is my first vehicle with automatic transmission, I quite it.

Here is the transmission after I cleaned it:


I’ll let you know how it all goes.

Cheers,
Hugo

 

[pugwash]

Douse it have the correct dip stick ,check how much oil it should take ,fill it up ,run it ,then dip ,its a long shot ,but possible that its being overfilled .pugs

 

[Hugo]

Thanks pugwash. I think that isn't the case, but I'll keep it in mind.
Cheers,
Hugo

 

[signwilson]

according to my auto trans guy they are the same gearbox as some of the fancy cars bmw and range rover internally I just put some transmission stop leak in mine ages ago still good

 

[stew]

Hi Hugo,
I can rattle through the usual leaks from that ZF 4HP22 , auto. Bell housing to trans body. End housing to trans body. Convertor seal , tailshaft seal. There is a lip seal in the speedo drive, the speedo drive body wears oval, o ring on speedo drive.
Main leaks were always from the oil cooling hose to banjo joints, banjo fittings distorted. Banjo fitting washers distorted.
Also, if the torque convertor is worn inside and/or the convertor support bush at the input shaft, oil pump end is worn, the convertor leaks down when standing. This overfills the trans level and oil pisses out , everywhere, overnight.

I suggest special attention paid to the oil cooler lines and the fitting surfaces. Notoriously nasty.

 

[Hugo]

@signwilson, thanks for the tip. Yes, it is used on a bunch of European cars. It even has it's own Wikipedia page which mentions that it "has been used in a variety of cars from BMW, General Motors, Jaguar, Land Rover, Maserati, Peugeot, and Volvo".

@stew, thanks for the list of suggested places where it can leak. That torque convertor leak down problem sounds pretty serious.

I'll do my rudimentary leak test before and after I replace some of the seals and see what happens.

Later I'll put the transmission and the engine back in the car and go for a drive and see what happens. At the very least I have learned lots from taking the transmission out and cleaning it. That knowledge should help if I need to fix leaks once it is in place.

BTW, how do you take the speedo drive out? I can't see that documented anywhere. It looks like this:


Does that 'C' shape unscrew?

Cheers,
Hugo

 

[Beano]

No. See the stud with locknut at the bottom of the photo ? Undo the locknut and back off the stud a few turns (or even right out, just to bne sure), them pull out the drive with a piece of plastic or wood used as a lever, or by gripping it with a pair of long nose pliers. I think you turn it first, to disengage the geared inside end from the gear inside. the trans. Hence the offset, cam-like appearance.

 

[Hugo]

Hi all


Thanks for that tip Beano, I managed to remove the speedo mechanism as you described.


It has two o rings on the outside and a small oil seal on the inside that runs on the 8.5 mm shaft. You can see the black seal here at the bottom of the mechanism:







The seal dimensions are 8.5 x 16 x 6.5.


It seems to be a very hard part to find. I have already tried my local bearing place, Alltranz, a local auto transmission place, EAI and ebay but can’t find a replacement.


Has anyone managed to source this seal?


Thanks in advance,
Hugo

 

[Beano]

Try Lewin in Brisbane...07....33534448. He can get just about anything and mail it to you.

 

[Hugo]

Hi all

@Beano, I asked Lewin today, but he doesn't have that part either.

It seems to be a particularly hard part to find.

Has anyone ever replaced the speedo mechanism oil seal?

Cheers,
Hugo

 

[pugwash]

is it actually leaking from the seal ,is the face of the seal that rubs on the shaft sharp or has it warn flat ,any chance you could match the inside diameter seal with one having a smaller od ,and make a spacer ring ,what other cars use this trans you may find the seal is listed as a merk, volvo or bmw part ,for example ,An old trick my father showed me was to shorten the little coiled spring that sits in the back of the seal to push it against the shaft ,a short term fix .pugs

 

[Hugo]

Hi Pugs

Thanks for the questions.

It was clear that the transmission had not been serviced for a long time so I decided to replace all its seals and o rings. For instance, the inhibitor switch o ring was so old it just snapped in two when I removed it.

I have already removed the speedo seal so I'm not sure what state it was in exactly as removing it resulted in it being mostly destroyed.

There is a seal available that is 8.0 mm ID instead of the original 8.5 mm. It is close, but I'm hesitant about using it since I don't know how likely it is to work. I am holding that option is reserve if I run out of alternatives.

What do you mean by a spacer ring? Would that be if using a larger OD new seal than 8.5 mm, such as 9.0 mm? I am guessing it would require a metal lathe which I don't have unfortunately.

Yes, many other car manufacturers used this trans (a ZF 4HP22) such as BMW and Land Rover, but unfortunately the speedo part is in the rear housing which differed between manufacturers. I suspect this rear housing and it's speedo mechanism were designed and made by Peugeot.

Thanks for your father's coil trick.

I'm wondering what others have done when needing to replace this seal.

Cheers,
Hugh

 

[Beano]

There are people who specialize in importing odd-sized seals. I have a number here but can't find it right now, but Google may reveal some. If you give them the dimensions they may come up with something.

 

[Hugo]

Hi Beano

I have done a lot of googling for the seal itself (8.5x16x6.5) and just did a bit then for specialist seal importers. None jumped out at me as likely solutions.

If you find the number and can let me know that would be great.

Also, if I find something I'll post it here for posterity.

Any other tips also appreciated, especially from someone who has actually worked on their 505 auto transmission.

Cheers
Hugo

 

[Pug72]

Hi Hugo

I sourced a full gasket/seal kit for my ZF3HP12 from overseas - in the US actually. A place called Cobra Transmissions. Very easy to deal with and delivery was about 10 days (might be a little longer with Kung fu flu around).