Yamaha 50 not pumping water

[deanc777]

I noticed when i went out last night that my outboard was not pumping water. so i stopped and gave some revs but it didnt clear. so i took the case off and the hose connected to the motor and blew through it then put back on. 10 minutes later started engine and it was pumping fine but on the way back to the boat ramp water was only just trickleing out. Buzzer didnt sound so it musnt be overheating??? any ideas

[jb123]

try when running to clear your pisser line, i always use a heavy gauge monofilament fishing leader..run it up the outlet as far as you can,usually where it enters the block at the fitting it clogs..sounds like you may have picked up some sand etc and clogs at the smaller orifices.

[Ken]

dean,
Take the hose off from the nipple that snaps into the lower cowling. Hang (tape) the hose over the edge of the lower cowling so that it points downward. Run the motor with the earmuffs on the driveway - garden hose wide open.
Push small diameter wire (or mono) thru the hose nipple to clear of any debris - you should be able to see thru it.
Debris (sand, shell, bits of weed) that you pick up in the water will collect at the hose nipple since it is smaller than the inside diameter of the hose.
Good luck [img]smile.gif[/img] ,
Ken K

[deanc777]

THANX have tried all that an hour ago and the water is only dripping out instead of streaming. any other ideas???

[Ken]

dean,
At this point I can't tell if you have a clogged up fitting or a bad water pump.
Take the hose off at the fitting on the block and clean out like jb recommended - check the hose and nipple connection again. Run the motor with boat in water - not with earmuffs. If you still can't get any water out the side discharge tube, then you have clogged up water jacket or bad pump.
Do you have a temp gauge or water pressure gauge? What year is motor? When was last time water pump impeller replaced? Sould be done about every three years.
Also, check the overheat alarm - it could be bad and not signaling an overheat condition. Disconnect the bullet connectors from the thermo switch and short them together (ones that go back to ignition contro) with the ignition switch on (motor not running) - alarm should sound.
Good luck, and let us know what you find out [img]smile.gif[/img] ,
Ken K

[Clive]

Sounds as if the impeller is breaking up to me? or the pump is on the way out? I dont know if you can back flush the motor?