yamaha 40hp xwt cooling problem

[gazzabuck1950]

Hi from Brisbane Australia,

I have a 2000 40 hp model xwt. When trying to last start it, there was no water coming out of the tell tail. I checked for a blockage in the tell tail pipe and it was fine. I then replaced the impeller, re-assembled and still no water discharge. I then removed the thermostat, placed it into a container and poured hot water over it and it opened. Re-assembled but still no discharge.

I then put the hose onto the discharge pipe and water came out of the intake on the lower leg.

Is there something I am missing, or is it time to go to the local marine mechanics?

Gazza

[99yam40]

I then put the hose onto the discharge pipe and water came out of the intake on the lower leg.

Not sure what you did here,what discharge pipe?

Did you replace the water pump with the kit or just the impeller?
the cup and wear plate get grooved and do not seal off well.

Also inspect the plastic housing for signs of melting, if any, replace the housing

Might try blowing compressed air up the tell tail 1st while running to see if that will move something around that is blocking a passage inside

[gazzabuck1950]

yamaha 40hp xwt cooling

Thanks for replying.

By the discharge pipe, I meant the hose leading from the motor to the tell tail outlet.

I only replaced the impeller, but have now ordered a complete kit. I thought everything looked ok, but may have missed something.

I also read on another site to remove the thermostat and try running to tell if the thermostat is the problem. If so replace the thermostat. Does this sound right?

Will let you know how I go.

Gazza

[99yam40]

Stat has no interaction with the tell tail, water come out when stat is closed or open
but you can pull and test or replace stat as Yamaha recommends every few years to make sure proper temp of motor

[gazzabuck1950]

Thank You

I purchased a whole impeller kit this time and a housing/cover (there were only 2 in australia and I had to wait this long to get it).

Purchased a flush tank, fired the motor up and *** what a water flow from the tell tail. Just goes to show, you should not cut corners. When I inspected the housing, it did show signs of melting.

Any way, thanks cobber for your advice. (in AU a cobber is friend)

Gazzabuck