KDXRIDER.NET

Dear fellow KDXERS,
How much resistance should the water pump impeller have? How about the gear on the backside of the bearing?

When I tighten down the impeller nut to spec and the clutch cover removed, the impeller shaft is almost impossible to turn. When I turn the gear behind the bearing it either tightens up so tight it stops or if I go the other way the shaft unscrews from the impeller nut.

Did I install the water pump seal incorrectly? I did it months ago and forget exactly how I did it.

How can I confirm my water pump seal is installed correctly before I reassemble the rest of the engine?

Hmm,I wonder what the problem is. It should turn fairly easy with the cover removed the engine.

Yeah I'm pretty sure I have it installed just like that diagram...I even followed the fellow KDXer who posted directions with all the pictures.

How easy would you say it should turn? I know it's subjective....but like I have to strain to spin it. Like if I flick it, the whole cover moves across the work bench before it spins. I estimate about 15 to 20lbs pound of force to spin it.

Your water pump seal is not installed correctly. The impeller is bottoming out on the housing instead of using the spring's pressure to hold it against the impeller. Press it in until the metal lip is flush with the case. This is all laid out in your service manual, be careful on install, the mechanical seal is graphite and quite brittle if you press on it. You need to press the housing only. And dont forget the o-ring under the impeller! It doesn't appear in any parts diagrams, only the service manual.

Oh ok....guess I'll start over , thanks Slick Nick!

Update....Hey Slick Nick! Upon further inspection I discovered that the metal cup was not full seated down onto the step. So after some careful pounding, I got it in.
Thanks again!

Glad you got it fixed!