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86 K-75 fuel pump


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So I bought an 86 K-75 that hasn't been run in 10 years. I poured out the 2 gallons of yellow liquid that was in the tank and put in fresh gas. (I also change every other fluid and filter before I tried to start it)

No gas comes out of the rear tube while cranking and I don't hear the pump turning. The next thing to do is to put power directly to the wires going to the pump and not the fuel gauge. But I suspect that the pump is gummed up and just need to be taken out and cleaned.

I found the fuel pump. Do I call my insurance company and tell them my tank was stolen? Please tell me that thing isn't bolted in there!

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I don't profess to be an expert on old K bikes, but I have worked on a few of them...


The pump is in the tank as you have found out, and is held in place by a plastic ring with two tabs locking it into place. Remove the fuel filler lid and then reach into the tank and squeeze the tabs and lift the pump out. Don't forget to disconnect the fuel hose too.


Likely, you will need a new pump and fuel filter. If any water was in the tank, the pump likely rusted and siezed up. If water got into the injectors they may be ruined too.


Good Luck with the repairs.


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Well I reached in and pulled the pump out. There seems to have been a rubber gasket between the tank and the pump. Unfortunately it almost all turned into tar. I've never seen such a mess.

Where can I get parts for 40% off of list?

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I just looked up how much parts are going to cost. $870 for the pump, vibration ring and three injectors. I was kind of suspicious that the blue book was so low on the K-75. Now I know why.

So my Sunday afternoon dilemma is, ask for my money back, cut my losses and part it out, fix it and see if this thing can bleed me to death.

I though Harley parts were overpriced, but BMW is insane.

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Go to ibmwr.org there are several good tech support articles available there. Which includes after market replacement parts for fuel pumps and fuel injectors. The mounting parts are only available from BMW. Good Luck.

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Great supplier for used K bike parts--www.beemerboneyard.com. I recommend them highly. K75s are fairly easy to work on, have a reputation for durability and long life, and are reasonably small and flickable. Once u resurrect yours, you may come to really like it. Good luck with it. Ride safely.



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I've used http://www.euromotoelectrics.com/ for parts on my old R80, and wouldn't hesitate to contact John and company for K bike parts needs. www.beemerboneyard.com is also a great place to get parts from. If I remember correctly, Chicago BMW Motorcycles gives something in the neighborhood of 10-20% of list price for parts you can't source elsewhere.


You're not alone in finding the dreaded tar ball at the bottom of the fuel pump (the thing that used to be a rubber gasket). Most of the current "fuel pump upgrade kits" simply substitute the K1100/K1200 pump, screen, and damper for the older parts. Its what I did on my K75S, and its running flawlessly. If you're going through the trouble to renew the fuel pump, I'd take the time to also replace the fuel lines (both supply and return), and also the vacuum line from the injector to the regulator. The aforementioned job of line replacement is a 'non trivial' operation. If you're not a sure hand with a wrench and a repair manual, don't try it.

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I bought a complete fuel pump, hose and filter kit from beamerboneyard. It arrived today and I installed it this evening. It took about thirty second of cranking, but she started. It won't idle yet and the middle exhaust is cooler than the others. I think I'll send some injector cleaner through it tomorrow and see if it clears up.

It sure doesn't sound a thing like my Harley.

But it is back from the dead and I'm a happy guy.

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