Is there even a way to rebuild a waterpump?

[eriknetherlands]

I have a BMW branded water pump on my car, it is dated 1985. Somewhere I think it is kinda cool to retain it, however there is green rocky, powdery stuff inside. And it is very dirty, even after a bath in solvent+ an ultrasonic clean.
It was not leaking when I removed it.

I know I can get a new one for something like 50 euro or so, or 135 from the Dealer, but can I actually pull mine to pieces & replace the bearings and seals? ( and reassemble...).

If tried pushing the shaft out both ways with a press, but it won't budge with the force that I dare unleash on it: afraid I'll bend the housing if i go further.

If they can be rebuild, then ideally I'd like to do it, as it also gives me the change to tumble clean or vapor blast the water pump, while also cleaning out the debris inside.

Not trying to be cheap here, but wanting a clean engine to look at. Do new BMW parts actually have the logo on them?
If you all say dont sweat, ditch it, then I guess I have little choice

 

[alprada70]

I tried, but when I put the pump in the press the housing broke... and I did it gently... but it was all very stuck...

 

[OCCoupe]

There are instructions and illustrations in the blue books on how to rebuild them.

 

[mbmw]

I'm rebuilding WP from the M1 and the CSL race pump all the time. The hard part is to get bearings and seals. BMW used to sell these parts , but not any more. With most pumps it is less expensive to buy a new pump. Rebuilding is only worth on hard to find pumps from the M1, 2002tii or S14.

 

[wkohler]

There’s a guy around town I see regularly that has a business called “obsolete water pump rebuilders” and I can never catch the phone number. With the 2002tii pumps so expensive I thought about seeing if he could do them.

 

[mulberryworks]

I did a quick Google Maps search, and that business might be for well pumps, not auto water pumps. But maybe their skills overlap.

 

[eriknetherlands]

@OCCoupe; thanks for the hint. Indeed the tech books have it! ( should have thought of that)
Indeed the impeller should be able to be pressed off. I'll give it a secodn try, with more force. If the housing breaks, then the choice is made easy: get a new one.

 

[Luis A.]

I'm rebuilding WP from the M1 and the CSL race pump all the time.

Where do you find the required seal and other parts to rebuild these?