Old impeller stuck on shaft

[clop52]

Hey guys,

I've had the boat for about 8 months and after finally getting the new fuel tank hooked up and all ready to go i take to the river this past weekend. Well, the overheat alarm went off, shut it off, checked the oil, it was fine, cranked it back and trolleyed back to the dock.  I figured the water pump was going bad, so here i am. Got a new kit and as i am taking everything off, the impeller doesn't want to come off. After about 20 minutes of trying just about everything, i decided to cut the side props of the rubber impeller to relieve the pressure (picture) and still nothing. I'm getting a torch tomorrow and heating that up, but i figure i'll post tonight and see if anyone has ran into a similar situation and how they got around it.  Thanks!

[CLM65]

Looks like it still has the bushing and collar installed above the impeller.  Those will need to come off before the impeller will come off.  Worst case, you can cut/split the impeller, bushing, and collar if they are all stuck on there.  Just be careful not to damage the shaft.  You shouldn't need to use a torch to get the impeller off.  It is all rubber, so cutting it would be the way to go.

[fitz73222]

Just split it with a sharpened chisel and it will come off. Start at the top and split it downward. This was standard practice on old Mercs with a stuck impeller. The next challenge I've found on Yamahas is stuck woodruff key that needs to be removed to change the base plate and gaskets. Yamaha uses a woodruff key instead of the flat wedge style key that Merc and OMC changed to decades ago. Hopefully your key will come out.

[clop52]

Ok. I will try the chisel idea, thanks! I will be careful not to damage the shaft. I'd let you know how it goes.