Yamaha Water Pump replacement

[Britfish]

Broken down the water pump and in the replacement kit I got the pump plate and gasket which the whole unit sits on, but ! how do I get the old one off ? The keyway for the impella is stopping it coming off.
Do I need to change the pump plate and gasket ?
Thanks very much for any help given

[boats.net]

You will have to remove the impeller key, sometimes can use a set of side cutters(wire cutters) and pry key out and sometimes have to use a chisel and hammer it out.

[Britfish]

thanks - its brutal to get it out !

[mrpontoon]

sand the new key down a little so next time it will come out for you

[robert graham]

The key is shaped like a half-moon, so tap on one end and then the other until it "rocks" and loosens it...then it'll come out!....File new key a bit so it's not so tight, then put it in the groove with some marine grease so it don't get so stuck next time!

[phonfish]

I use a pair of visegrips to hold on to the key. Once I have clamped on to it,I hit the visegrip from an angle. It has worked on my twin f150s the last two times I have changed impellers.

[Britfish]

Thanks all for the advice !