Thread: Not the water pump

I'm aware of that, which is why I pulled the foot off. Everything Looks fine so i am back where i started.

Make double sure the pump is installed with correct rotation. I have seen them where they won't flip. Just had one on a guys motor last summer he put in backwards and didn't flip.

Originally Posted by wannabe fisherman

peeing on the muffs doesn't necessarily mean a lot, my engine pees even if not running when on muffs

It should because the water is under pressure from the hose and not the pump. A lot of people tend to turn the pressure up way too high when running on muffs and makes it appear the pump is working correctly.

What about the thermostat? Doesn't it have to be open for it to pee?

Originally Posted by fishingman

What about the thermostat? Doesn't it have to be open for it to pee?

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I don't think so. As I understand it, the tell tale hole bypasses the thermostat and just indicates the pump is working. The main water discharge from the block comes out the exhaust port on the back of the motor, I believe.

I would check the pump vanes to see if they are the correct width to fill the cup. It may have the wrong impeller installed. Or it could be the wrong diameter.
New pump maybe wrong one.
The only other thing I can think of is the water tube being cracked or bad seal.
Hope this helps.

I had picked up an oem impeller from the Yamaha dealer on the way home when the pump wouldn't work. The one installed looked new, but I decided to replace it with the oem one. May be my imagination, but the oem one seemed to fit tighter in the housing. To insure the veins were oriented correctly I put the impeller in the housing first then slid the housing over the shaft. I rotated the shaft so the key would align with the slot on the impeller and it slid right on. Don't know why I never thought to do it that way before. Takes the guess work out of the vanes orientation.I
I'll try it out shortly but it should work.

Not sure what the issue was but the OEM impeller did the trick.