K75 Oil/water pump rebuild question

[Recker1]

Hey guys - quick question on the pump rebuild process:

I am in the process of replacing the seals in my '93's pump and want to make sure I have the parts in the right place. When I got the impeller shaft removed, all of the spacers fell to the floor making it difficult to tell exactly where they went. My question is this - once the seals are installed and the shaft is through the seals, where does the smaller of the two spacers go? I know the large spacer attaches to the underside of the impeller but not sure about the smaller one. I assume that it just goes beneath the large spacer under the impeller - is this correct?

Thanks for your help...

 

[kentuvman]

Just got through doing mine on my '87 K75S - the seals were garbage!

Honestly don't remember those parts in your picture, but that doesn't mean much.

Besides reading a couple bulletins on how to do this on IBMWR, I watched this You Tube video a few times, which helped a lot.

Also, I didn't realize it, but had to replace the impeller to use the new parts.

I hope this helps:

http://www.youtube.com/watch?v=j8JUY8C2c08

 

[Recker1]

That was very helpful - thank you! I think the rebuild was a success!

 

[kentuvman]

I was pleased after riding 1,000 miles to Omaha & back to MN, NO LEAKS!

Before deciding to rebuild the pump myself, I'd called a BMW dealer who said they didn't rebuild the pumps anymore. In discussions with a friend, we both concluded today's mentality, not just just with motorcycles, is to replace with "new" instead of repairing what you've got.

The only thing that threw me was not being able to use the original impellor. I'd ordered my parts from Motobins, so when I found out I needed to order another Impellor, I lost a week.

But in the big scheme of things, a week is no time at all.

Glad the video helped!

Regards,

Ken

 

[ghyber]

K75S Water/Oil pump rebuild

Just noticed that I already had the new impeller/rotor on my 93 water/oil pump. What I do find odd is the fact that the bushing that is now sold with the new impeller is not as thick as the old one.

This will have an impact on space between the impeller and the pump housing and cover. Anyone care to comment and would you install the new thinner bushing or stick with the old bushing; I am replacing that corroded impeller.