Yamaha f200 heat up

[Elcasa]

Hi, I need help
My Yamaha F200xb 2014 was working fine until I changed the impeller in May 2018, the last time I used it was in March and the only time this year, when I left for the first time the engine started to heat up and the water jet by the exit it look like clog but was working fine before that. But when I flushed the water goes well. Then I changed the whole water pump (impeller, housing) but continued heated up. I checked the thermostat and it did not open well so I put a new one in it and I checked before to replace and was working fine it open at 158f temp. check the poppet valve and look good. Without the thermostat it does not heat up, and without the poppet valve and the thermostat set the water flow through the outlet improves but still warms up. Any suggestion.

 

[99yam40]

without the PRV in place the motor will not fill up so it will over heat.
RPV open will dump too much water at low RPM so the motor will never fill up to cool the top cylinders

 

[Elcasa]

I found out the problem
What happen I replace the pump and the housing with the kit but the kit did no provide the washers on top of the impeller, 3 washers that the one in the middle is like oval so that shape provide pressure to the impeller down and I haven’t replace since I bought the boat 2014, so replace all 3 washers and running fine now, I hope that help someone else.
Thank you

 

[99yam40]

Good to hear you motor is pumpg as it should again, but
The washers that sit above the water pump with the sleeve over them are to preload the gears in the lower unit, and should not affect the operation of the water pump.
need to lift up on drive shaft when installing the sleeve.
if you do not youo will hear gear rattle when idling in gear

seems they moved these parts from over the cup to under it on newer motors.
not sure what their purpose is now.
did you leave them out completly before or put the old ones in when it was not pumping properly?

 

[Elcasa]

They are now under the pump on top of the impeller, I place them ok when it was not pumping well and lift up on drive shaft when installing also, but this happen to other people also, the middle washer press down the impeller to avoid suck air and have low pressure water, I think.