Proceedure for changing water pump impeller

[Baja 252]

I have a 05 2.5 XS Optiimax with a Sportmaster lower unit that I need to replace the water pump impeller. I have never done this before, but I hear it's not to hard of a job. Can someone give me a step by step proceedure or direct me to one. Also, do I need to buy just the impeller or is their some sort of rebuild kit I should get.

Thanks,
Bill

[flabum1017]

First with the argument: I always get the full kit with the housing. It comes with evrything to replace the whole pump. Too many times the housing may be a little warped or a gasket deeper down has been sacrificed. Do all the gaskets and housing so there is no question of the integrety of the pump.

Get a service manual.

Procedure: Remove all the fasteners holding the gearcase on, remove the gearcase (it drops off with no hiddenn linkages). There should be a plastic guide tube that sometimes stays on the water tube....... be sure to retrieve it. Replace the pump and all the gaskets. When installing the impeller, slide the impeller onto the shaft and onto the keyway. Slide the housing down and turn the driveshaft clockwise as you push the housing into place over the impeller. Put the water tube guide on the pump and install the lower unit being careful to line up the guide with the tube. The splines on the driveshaft may or may not line up with the crankshaft, so you may need to drop the gearcase to turn the driveshaft a small amount until the splines line up. Make sure the water tube and shift shaft line up as you install the gearcaes. Bolt it up and you are done.

[whipper]

I did mine the first time last spring you should do it every season!! Its so simple you will be surprised!! none of this makes to much sence untill you drop the gearcase then its ohh thats this and thats that! It took me an hour my first time but after that you can do it all in about 20min no lie. Dont forget when your undoing the nuts and bolts to your gearcase theres the anoid nut hidden at the trailing end theres a hole and youll see it down there the the anoids up under your foil. That needs to be lock tightned back inplace after being cast, it will back off eventualy otherwise. I put a bit of lock tight on all of them just the blue stuff since I check the bolts regularly anyway. Make sure your motors tilted up a bit about half way is good because the shaft 20inches or so comes out with it. Thats has the splines at the other end like a drive shaft that you line up when you put it back up. thats the hardest part of the whole job. The little shaft your water tube for your cooling as mentioned needs to line up at the same time. You can do it your self easy enough but with another guy its easier to line up everything when you slap it back on. One guy holds the gearcase and the other lines up the tube and the shaft.You will be surprised when you drop the case theres nothing there but the water pump so its simple to see what you need to do just buy looking at the new parts and replaceing then were they mach up. One more thing do not over tighten the water pump screws the housing is just plastic so you can crack it you will feel the tightness when you unscrew them. just nice and snug tight like a spark plug. I believe the tourque for your gearcase nuts is 60lbs thats what I check mine for for pre run checks anyway. I dont have a manual and cant remember were i was told that but darn sure thats what is is. You better make a call to a merc sevice counter to be sure. Let us know how you make out. Just dive in youll see. PS you can use dish soap to twist the new impeller down the drive shaft clock wise you will see what i mean. Also the new gaskets need to be right side up look carfull and you can tell that also. Later James