Leaking water pump XTZ660 3YF 1992

[alexpezzi]

Hello guys I am in Italy, it's the last weekend, time to get back and I am stuck with a leaking water pump... It appears to be the o-ring as it drips from the small hole underneath the water pump assemply.
I can probably source the o-ring from a local tractor dealer tomorrow afternoon, the bike shops around here don't have it in stock and Yamaha Italia timeframe is embarassing.

As I never done it before, my question is (provided I find the part): you need to drain the oil before removing the water pump?
also... do I need to replace anything else apart the o-ring? (two o-rings actually).

The bike is the same old XTZ660 3YF 1992 (53k miles).

[alexpezzi]

Hello, a quick update... it seems that the oil seal inside the pump is the culprit. It's a strange oil seal held with a spring, I don't think it can be replaced with a generic one but I could be wrong. Is there a way to temporarily fix it? It needs to hold 1000 miles (Italy to UK). Yamaha only supplies the whole pump.

...self-reply to the previous post: yes, you need to drain some of the oil (about 1 liter) then remove the pump with the bike on the side stand so the remaining oil will stay on the left hand side inside the crankcase.

[jjrider]

It should be a two piece mechanical seal. The one side with a spring and rubber base the seals the bottom plus a ceramic flat top. the other part will be in the back side of the impeller it is a ceramic disc , the 2 ceramic parts spin against each other and that puts the pressure on the rubber base to seal. Don't know if a rubber washer under the base will work or not.