water pump problem

hello to all forum helpers.

first of all i am asking because searching in the forum is not available wright now.

I rod my bike today (WR426 2001) and notice a little drops come under the water pump (their is a hole under the water pump side cover which water came out from their), check the oil and it is OK (new oil), not milky.

All the ride was for 20 minuets.

what parts do i need to replace and what to be disassemble?

do i need to drain the oil for getting the impeller out?

thanks for all helpers. :devil:

The seals on your impellor shaft are in need of changing. Not a big deal, but it needs to be done. I believe there is a write-up floating around that details how to do it...SC

The seals on your impellor shaft are in need of changing. Not a big deal, but it needs to be done. I believe there is a write-up floating around that details how to do it...SC

do i need to remove just the water pump cover or the right side crankcase either? (that means that i will have to drain the oil?)

on the 450s, you will need to remove the right side cover, which means draining the coolant and oil. i imagine its the same for the 400s.

it's easy to do. you'll need to replace the water and oil seal for sure. you'll also probably need to replace the impeller shaft too. when the search engine works, you'll find a lot of info on it. you can find the part numbers at the yamaha website.

If you have a manual, it should detail the whole process. If you don't, you can download one from the sticky thread at the top of the forum...SC

Having the same problem on my 450. I needed to change the impellerchaft as well, since the previous owner didnt mount the oilseals right! So if it seems to have any kind of wearing issues i rec u change it, or else you might find the problem returning faster than you want to!

take apart today the side cover and try to open the impeller.

now the problem is that the impeller is stuck.

when trying to opened it with the proper tools: spanner and 12mm socket, it seems to have tiny cracks around the impeller nut.

now i don't have a choice and replace the impeller, but how do i open the impeller???

Did you use a hexagon socket or dodecahedron socket? (BTW, never use spaners... Its the tool who have destroyed most nutheads ever! Even a swiss armyknife is better.. almost..)

You did turn counterclockwise?

If the impeller is unusable anymore i suggest you cut it loose.. Be shure not do damage the screw threads on the impellerchaft..

Did you use a hexagon socket or dodecahedron socket? (BTW, never use spaners... Its the tool who have destroyed most nutheads ever! Even a swiss armyknife is better.. almost..)

You did turn counterclockwise?

If the impeller is unusable anymore i suggest you cut it loose.. Be shure not do damage the screw threads on the impellerchaft..

i used 13mm wrench on the flats shaft and 12mm hex socket wrench, i did turn counterclockwise.

i ordered new impeller from TT-SHOP,so no need with the current.

i will try to cut it without damage the shaft.

visibly, the shaft don't have any wear on it and their is no free-play (the bearing seems to be OK).

what is the best Way to cut the impeller off without damage the shaft?

a dremel tool with a cutting disc would be ideal if you have one.

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