ATF leak at speedo drive

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REman
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ATF leak at speedo drive

Post by REman »

Hello All,

Have had long time issue with ATF leak at speedo insert at tranny. All parts are listed as NLA but have found an O'ring by dimensions from realoem on Amazon, but that has not solved the problem. The issue I believe may be that bushing on the inside of the plastic housing the cable goes into (see #24 from RealOem diagram link attached), mine is not good. If anyone has had same issue and hopefully solved it, would be great to know how.

No more E12's to be found in local salvage yards for years now in the Orlando area, and can't find replacement anywhere yet.

https://www.realoem.com/bmw/enUS/showpa ... e_vignette
'81 528i... mfg date 10/80...owned since 1990
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Mike W.
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Re: ATF leak at speedo drive

Post by Mike W. »

Looking at the diagram it looks to me like there should be another seal or O ring or something. The O ring #20 would seal the outside of that tube, but not the shaft of #19. Maybe the bottom most of the 4 that are part of #24? And I tend to forget about the obvious sometimes, how about checking with a tranny shop? Wouldn't hurt to ask, they might want to sell you a full rebuild but they might scratch their head and say, oh yeah, all you have to do is ...

Also found this https://go4trans.com/speedometer-3hp22/ which may or may not even exist, and note that they say the image is generic.

The good news is they used that tranny in a bunch of different cars back in the 70s and 80s. The bad news is the BMWs are probably about the only ones that are left, at least on this continent.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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REman
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Location: Orlando FL
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Re: ATF leak at speedo drive

Post by REman »

Thanks for the tips Mike, as always helpful!
I believe the inner seal looks to be there in the diagram of the whole assemble without a part #. The bottom arrow coming from #24.
'81 528i... mfg date 10/80...owned since 1990
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Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: ATF leak at speedo drive

Post by Mike W. »

Sometimes bearing shops will surprise you with what they carry if you can get it out without destroying it. Again, all they can do is say no.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
dutch
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Joined: Sat Apr 15, 2023 8:22 am

Re: ATF leak at speedo drive

Post by dutch »

Hi there, Not sure if your problem has been fixed yet , but I`d visit the local bmw dealer and just ask for that size o-ring :?: Looks like the ones you need are 19x1.8 mm. That size is pretty common overhere in Europe and it`s also used on the 120i and I`m sure many more bmw`s.
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REman
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Re: ATF leak at speedo drive

Post by REman »

Thank you for the tip, worth a try!
'81 528i... mfg date 10/80...owned since 1990
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