water pump issues

[gpaxson1]

my son bought a 1989 15hp yamaha 2 stroke motor.
ran motor in garbage can it wont pee when running
cleaned water lines, they are all clean and free flowing
installed new water pump kit with all gaskets, new tstat, reinstalled lowwer end unit, ran motor still wont pump put muffs while it was in garbage can full of water, and water started flowing, out pee hole. pulled muffs off and the water stopped peeing ( 16yr kidd is bummed ) please help if u can
thanks.

[TownsendsFJR1300]

Can you please clarify?

Your super long sentence is hard to figure out EXACTLY between the muff's / can etc is happening..

But quickly, did you make sure the impeller "arms" were bent in the correct direction while assembling? Any over heat damage to the main housing will cause issues..

[robert graham]

I think he's saying the motor pees while on the muffs but not in the water drum....

[TownsendsFJR1300]

I think he's saying the motor pees while on the muffs but not in the water drum....

Thanks Robert.

Me tinks something isn't assembled quite right...

Should be just the opposite..

[gpaxson1]

Water pump issues

Let me start again
When he got the motor home we installed the motor in a garbage can and ran the motor, the motor would not pee out.
So we dropped the lower end unit and replaced the water pump with a new kit.
Also we flushed the water lines to make sure there was no blockage, everything was clean. We also replaced the Tstat to make sure it wasn't stuck closed.We reassembled the lower end unit and ran the motor in the garbage can again, still didn't pee out just spitted a little water, I installed motor muffs on the lower unit it started pumping water. So I pulled the muffs off it keep pumping water, after turning the engine off and restarting it would not pump again

I installed the pump right, I have replaced several water pumps on my 150 Yamaha 4 stroke
Would like to know more about the overheating thing

[99yam40]

you have not said it was having a overheat problem only a problem with the tell tail water flow.

Maybe the lower unit is not set low enough in the water to pump properly.
Hard to tell from this side of a computer.

as was mentioned before the plastic housing can have problems if it was overheated in the past.

and when you said kit I guess you replaced the cup and wear plate also, even though you did not say those parts.?

[gpaxson1]

No problem over heating
Lower unit sitting in garbage can on boat at water level as if the boat was in the water.
Replaced everything except the housing ( cup, gaskets , impeller , plate )
That's what I was saying about overheating
I didn't know the housing would go bad.
Never had a problem with a housing
I will get one tomorrow and try it
Question would the housing being over heated make it suck air. Cause a friend mentioned it might be sucking air at the pump.

[99yam40]

look at the housing very carefully. plastic tends to melt and distort.
I have seen rubber dampeners and the metal support get out of wack on some motors also due to corrosion. But have no idea if yours has that or not.
and too lazy to look tonight

[TownsendsFJR1300]

From your updated description, the WP isn't pumping, the muffs are forcing water to the power-head.

But members here had similar pumping issues and that housing was warped, just a little and wouldn't pump enough....

While the LU is off again, I'd re-check gaskets, o-rings and the water tube going up into the power head.

If you don't have a manual, check the parts fisch above(Purchase Yamaha Parts in RED), bring up your engine and compare making sure your not missing anything. The PO may have installed some part incorrectly, or left it out..

http://www.boats.net/parts/search/Ya...201/parts.html


Good luck and please post back

[99yam40]

#15 was what I was thinking about, but there was a rubber dampener with that guide

GUIDE, SEAL DAMPER