Author Topic: K75 Oil Leak and Clock Issue  (Read 3164 times)

Offline Smudgemo

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K75 Oil Leak and Clock Issue
« on: August 04, 2025, 10:41:14 AM »
I have a '92 K75 RT that has been sitting for nearly 20 years back on the road and working well, but a few things still to work on.  One is the clock.  It was very faint so I followed the instructions to clean the connectors as outlined in an article on The Internet BMW Riders site, and it's pretty good but doesn't display a few numbers well.  I'm wondering whether it's worth going back in and working the connectors again.


The other issue is oil leaking from the filter cover plate.  Couple of drips each night in spite of a new o-ring (and I'm starting to think I know why the prior owner broke one of the three bolts which took this bike off the road originally..) I'll wait until the next oil change, but other than a fatter o-ring, I'm not sure what to try.  I could maybe flatten the cover on some 600 wet and dry on my granite surface plate, but not sure that'd do much.  This is what the pan looked like when I removed the broken bolt.

  • '92 K75 RT / '08 GS
-Ryan

Offline Laitch

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Re: K75 Oil Leak and Clock Issue
« Reply #1 on: August 04, 2025, 02:35:32 PM »
The OEM o-ring should seal if the cover isn't over-tightened; otherwise, it's liable to leak. The cover screws are torqued to only 6±1Nm.You mention flattening the cover. Is it warped? I wouldn't mess with it unless a straight-edge shows it is. I'd probably replace it if it was.

Verify that what you are seeing isn't oil coming from the circled port of the water/oil pump (photo below) that is then blowing rearward onto the cap during riding.


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  • 1995 K75 102,000 miles

Offline Smudgemo

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Re: K75 Oil Leak and Clock Issue
« Reply #2 on: August 04, 2025, 03:06:03 PM »
Definitely the cover from what I can see.  I stuck a Qtip in the weep hole and it's just some road grime.  The leak is getting worse, though.  I just remembered I left the bike in the drive with nothing under it and there was already a spot of oil an hour later with more ready to let go.  I gave the three bolts a quick check and they're not too tight, but maybe previously they were over-torqued which led to the broken bolt by the PO.  Maybe it leaked and he tried to snug things up a bit?  Who knows.

I guess unless there's another suggestion, I'll just keep cardboard under the bike until I do an oil change and can give the cover a better look.

As for the clock, I think I'll leave it for now.  Good vs Perfect and whether I want to potentially break something that's made of 33 year old plastic.
  • '92 K75 RT / '08 GS
-Ryan

Offline frankenduck

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Re: K75 Oil Leak and Clock Issue
« Reply #3 on: August 04, 2025, 04:17:15 PM »
Clock LCD: Segments can die over time. The clock only has two contacts: + and -. Recleaning them won't fix the LCD.

Oil cover: Add a light coat of RTV.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline Smudgemo

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Re: K75 Oil Leak and Clock Issue
« Reply #4 on: August 04, 2025, 04:49:25 PM »
Works for me. 

Thanks fellas.
  • '92 K75 RT / '08 GS
-Ryan

Offline Past-my-Prime

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Re: K75 Oil Leak and Clock Issue
« Reply #5 on: August 05, 2025, 07:06:52 PM »
I find that changing the oil, the thing that is most important and takes the longest is making sure that the cover and o ring are absolutely clean and pristine, not a tiniest speck of grit or sand allowed!  Otherwise I also get an oil drip after changing the filter.
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Offline Stuadh

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Re: K75 Oil Leak and Clock Issue
« Reply #6 on: Today at 12:33:52 PM »
The OEM o-ring should seal if the cover isn't over-tightened; otherwise, it's liable to leak. The cover screws are torqued to only 6±1Nm.You mention flattening the cover. Is it warped? I wouldn't mess with it unless a straight-edge shows it is. I'd probably replace it if it was.

Verify that what you are seeing isn't oil coming from the circled port of the water/oil pump (photo below) that is then blowing rearward onto the cap during riding.



So, if the leak WAS coming form the ringed hole, how would you fix that?

I've got a leak from a previously dry bike and it seems to be coming from that hole.  Should it have an allen bolt in it?  Mine doesn't.  I've just done an oil and filter change fitting new seals all round to no avail.
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Offline Laitch

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Re: K75 Oil Leak and Clock Issue
« Reply #7 on: Today at 01:55:45 PM »
You seem to be indicating a leak from the weep hole of the combination oil/water pump. The oil seal on the pump shaft could be worn and now defective. A bolt should not be installed in the hole because the hole is there to indicate seal defects.

If this Brick hasn't been ridden very much, take it out for a 100k ride. The seal might swell and stop the leak. If this machine is regularly ridden, the leak means the seal is degraded. If it is only depositing a drop or two on the floor overnight, I personally would keep riding until it gets worse, but denial is usually my choice of treatment for most mechanical problems until riding season ends and there is six months of idleness when I can work on the condition. What you don't want is a self-oiling rear tire. 
:laughing4-giggles:

Here's a photo from the front of the engine showing the pump cover and location of the weep hole. I think we're discussing the same location.


  • Along the Ridley in Vermont.
  • 1995 K75 102,000 miles

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