i abrasive slurry pumps

Yamaha F250 water pump procedure

mills asks:

I have a 2009 Yamaha F250BTXR motor and I am going to replace the water pump impeller. Done this before on many other motors but I have a procedure question. Rather than leave the shift in Neutral for the procedure I was thinking that I should put it in Forward or Reverse before beginning. My thinking is that if the driveshaft splines do not line up exactly I can turn the prop to move the driveshaft to line them up. If I was in neutral turning the prop will not move the driveshaft. Is this a good idea or is there something I am missing??? Thanks

boscoe responds:

Leaving it in neutral is the normal procedure. The lower unit can be rotated a tad one way or the other if needed to get the splines to engage. Also, the flywheel can be rotated a bit if needed.

Having said that, if the shift lever is used to put the motor into a gear, and the shift mechanism on the lower unit is not messed with, that should work as well. You might find yourself having a hellava time turning the drive shaft via the propeller shaft.

Blue_Sky responds:

I would def leave in neutral. If it's not lining up you can usually back the drive out a bit and turn the driveshaft clockwise a nudge with a rag in your hand for better grip, obviously not easy fighting the impeller and holding the drive with one arm, but done it many times. You will have a hard time finding the ideal shifting spot if you put it on in gear, will easily go into one and not the other once shifting from the helm, at least my experience. Will end up taking it back off to put it on in neutral to give the shift shaft the right 50/50 buoyancy between gears. You will also find after shifting the drive into gear once it's off the engine, it's a pain to get right in that ideal neutral spot again. I've found it's best to take off in neutral and just not touch it.

mills concludes:

Guess I better leave it in neutral!!