water pump

[yfz450les]

i have an 04 yfz450 and it is leaking antifreeze out of the water pump very slowly but u can see it on the ground and i was wondering wat part do you buy like off of ronnies to fix it from leaking???

[RYAN44]

You need to get the two seals shaft and bearing to fix it good

Most leak till the motor worms up because once it worms up the seal expands and seals enough.

[Toadz400]

Originally posted by nacs420
Most leak till the motor worms up because once it worms up the seal expands and seals enough.

It's a problem with the '04's. Do a search on YFZCentral and there are some good instructions on how to do it.

[jshtex]

I think it is a problem on all of them, at least up thru 06, I know of two of them (06's) that have failed. Maybe the 06 owners don't know it because yami installed a hose from the drain hole to back by the swingarm.

To me it's really not that big a deal to fix and I carry a complete kit to replace the water pump to every race now.

[jrspawn]

Its an issue with pretty much every 4 stroke yamaha engine since the YZ400f. Very easy and cheap fix also, most times all the is needed is the outer seal facking the water pump. Be sure to inspect the shaft and bearing for and scoring or play. I have Never yet found a bearing, inner seal, or shaft to go bad myself just the outer seal and ive had quite a few yamha powered quads. Yes most recomend replacing that whole assembly, but most times it is not needed, just a simple seal replacement. Make sure you install it correct and add a little grease to it, they sometimes come packaged with a little in them.

Thank you
Justin