Tohatsu 2-stroke impeller

[Norwegian Wildcat]

- We've inherited an engine (M8B) which was apparently serviced and had a new water pump impeller installed a couple of years ago. It hasn't been run since.
- Routine service just completed and tank test run - all great except there's no water exiting the check port.
- All pump components, incl impeller & gasket, checked and in apparently good condition.
- The impeller was installed anti-clockwise (we believe this was incorrect). We have tested - briefly - in both positions, but still no luck.

Rookie question: any advice what else to look for?

Thanks!

 

[racerone]

Put more water in the bucket ??----Must be 8" above the impeller.

 

[MattFL]

As mentioned above, if you're using muffs now, first test it in a bucket or barrel of water, and the water level must be above the water pump. If it works in the barrel but not with the muffs, then your muffs aren't delivering enough water, probably because your hose isn't giving enough water.

 

[Norwegian Wildcat]

Hi, and thanks for the replies. I must say I feel a bit silly since I have now tested with more water in the tank, above the physical location of the pump casing, and it is now pumping the water fine. the M8B seems to need more water than the MFS6 4 stroke that I am more used to. Thanks again.

I have installed the impeller with a clockwise turn of the driveshaft which is opposite of the way it was installed when we got the motor. Can somebody with more experience than me confirm that this is the correct way?

 

[MattFL]

Drop the lower unit, inspect the impeller to be sure you didn't harm it running it dry. Then put the gearbox in forward gear and turn the prop forward with your hand. Which way does the shaft turn? This is the way you should turn the shaft when lowering the cup over the impeller. Put a thin layer of grease on the inside of the cup and wear plate.

 

[pvanv]

BTW, the impeller will flip into proper orientation as the motor runs.

 

[TOHATSU GURU]

So the impeller is basically orientation fluid? We have come so far in water pump orientation