water pump problem, PLEASE HELP

9 replies to this topic
  • yzf_virgin

Posted August 13, 2002 - 09:52 PM


How bad is it that the motor end of my impeller shaft broke off and I can't find it? I assume it fell down in behind that gear that it sticks into. Are there moving parts down there that it could jam up? Secondly, I want to replace the seals while I am in there and I can't seem to get them to come out. It is as though they are glued. Is there a trick. Thanks in advance for all of the help.

  • Hick

Posted August 13, 2002 - 10:50 AM


It don’t stick into a gear, it has a squared off end that fits into a notch on the end of the counter balancer shaft. So maybe the end didn’t break off. Hmmm?

But if it did indeed break off then it is rolling around by the main gear or clutch basket, so you need to inspect the counter balancer shaft for damage and fish the part out, ergo you need to remove the right cover. Assuming you have the pump cover out of the way all you need to do is remove the brake pedal, kick starter, and lower oil delivery line. Then you can remove the cover (Hint: the two clutch cover bolts at noon and 1 o’clock extend into the case so they need to come out, as does the top right oil filter cover bolt, but the round clutch cover can stay on).

If you have the case out you can get at the seals from the opposite side. If on the other hand you realize that nothing is wrong with your impeller shaft and therefore avoid the hassle of removing the side cover I’d say just stick a screwdriver in the seal opening and pry up the other end.

What other seal are you talking about? The inner pump shaft seal will only come out if from the other side so the cover does need to come off. The pump bearing may also need to come out first, I forget. Unless you are getting coolant in your oil that seal is probably okay.

[ August 13, 2002: Message edited by: Hick ]

  • DaveJ

Posted August 13, 2002 - 07:17 PM


I have mine apart at the moment. Outer seal toke a dive on the last ride and out came my coolant.

If the shaft did break, which I doubt it, you had better find it. It could become a worthy problem for ye internals.

And I know for sure that the right cover has to come off to get the inner seal and bearing, but it also seems like the cover has to come off to remove the shaft as well.

Best to follow Hick's advice.


  • yzf_virgin

Posted August 14, 2002 - 12:39 PM


Thanx guys. I already have the right cover off. The end of the shaft has definitely broken off. I was unable to find it. I will assume it came out with the oil because there is nowhere it could have gone behind that counter balancer shaft gear, RIGHT? Also, I still can't get the seal out. I've tried prying it with a screwdriver and even pulling it with needlenose. What next?

  • Hick

Posted August 14, 2002 - 01:28 PM


Look inside your magneto. You need to find that piece. Just as important, you need to figure out why it broke to begin with. Maybe the shaft somehow seized in the bearing? How does the end of the CB shaft look? How's the pump bearing look? Impeller? Pump cover?

You can cut the seal out, I've done this on my p/u a few times, never had to resort to that on my bike though. Be careful you don't bugger the case where the seal sits. Try getting the spring with a pair of sidecutters or snips, then cut the seal carefully with a penknife or exacto or something.

You may try a few different solvents to unstick whatever it is that is holding it in there. Corrosion from running straight, hard water??

Hope this helps.

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  • Hick

Posted August 14, 2002 - 01:33 PM


Originally posted by DaveJ:
it also seems like the cover has to come off to remove the shaft as well.

Yeah, you are right about that, there is a piece on the shaft that butts the bearing and prevents it from “riding out” and causing the impeller to hit the pump cover.

I just can’t fathom what would cause that part to come under enough stress to actually break. The only thing I can think is it seized in the bearing.

  • DaveJ

Posted August 14, 2002 - 06:45 PM



That's what I was trying to figure out, unless something hard went floating through coolant system.



  • freestyle111

Posted August 14, 2002 - 07:08 PM


if its not inside counterbalancer shaft you should get a magnet probe and start fishing from ignition side.theres a good chance its stuck to flywheelsince its heavily magnetised.if you still cant find it pull off clutch basket lay bike on side so flywheel is facing ground and start flushing engine from clutch side.the square end of impeller shaft is defintly large enough to do some serious damage to motor and i can almost guarantee it will.

  • Shawn_Mc

Posted August 15, 2002 - 09:56 PM


Talk about free radicals! A nice hardend piece of steel floating around your transmission is a bad thing. It might be worth your while to split the cases now, that to HAVE to split them later, and possibley have to replace one or both because an arguement between the trans and your "floater". If it was me, Id split the cases. The consequences are too great for the gamble. Just my opinion.

  • yzf_virgin

Posted August 15, 2002 - 01:29 PM


Oh happy day! I found it and boy am I glad because it is twice as big as I thought it would be. It definitely would have ended up somewhere BAD. I got my seals put in and I will have my new impeller shaft tomorrow. Thanks again for all of the help. And don't worry, the shaft broke due to my incompetance. I should be in good shape now.

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