2006 YFZ450 Water Pump

[tsargent4]

Just curious, I have noticed that a small amount of Engine Ice has collected on my belly skid plate below the motor at the rear of the motor. I have noticed that if you stand the atv up on its rear and take the belly skid off, that there is a small, almost pea size hole on the underneath side of the water pump. Is that hole a "overflow" or what is it? I believe that is where the coolant is coming from and I asked a friend and his motor has this hole as well. Any info would be appreciated. Thanks.

[mxraptor149]

The hole you are referring to is called a "weap" hole. This hole serves one primary function: When components of your water pump fail (impeller shaft, seal, etc.) coolant will begin to leak or "weap" out, signaling that you need to replace your water pump.

[400exMO]

Yep seals bad or some other water pump component. Don't quote me on this, but if you do not fix them soon coolant will eventually leak into your crankcase.

[yfzfelix]

Originally posted by mxraptor149
The hole you are referring to is called a "weap" hole. This hole serves one primary function: When components of your water pump fail (impeller shaft, seal, etc.) coolant will begin to leak or "weap" out, signaling that you need to replace your water pump. you don't need to replace the water pump, pull the cover off, remove the waterpump impeller and there is a seal on the shaft, when you go to Yamaha they have 2 seals that go on the shaft, the seal behind the impeller is the outer seal, thats the one that usually goes bad, if you get anti-freeze in your oil thats the inner seal, good luck with it, Steve

[tsargent4]

when you say pull the cover off, you are referring to the water pump cover itself, nothing to do with the clutch cover or case?...

anyone have torque specs for the impellar and the water pump cover bolts?

[coryatver]

The seals go bad becuase the shaft is messed up. You need to replace the shaft and seals or the seals will just go bad again. There are aftermarket shafts that are soposed to last longer.

[yfzfelix]

Originally posted by tsargent4
when you say pull the cover off, you are referring to the water pump cover itself, nothing to do with the clutch cover or case?...

anyone have torque specs for the impellar and the water pump cover bolts? you are rite, the water pump cover, if you send me an e-mail to yfzfelix@yahoo.com to remind me I can look up the torque specs in my Yamaha manual tomorrow for you, I see some one says to replace the shaft but if it was me I would do the seal first and see if thats all you need, I have replaced the seal on my 05 2 years ago and it has not leaked a drop sinse, Steve

[tsargent4]

ok...ill try that when i get the chance...