Impeller change problem...1964 Merc 50hp

[Cpt.Justice]

I have a 1964 Merc 50hp serial#1717021. Ok, today I went to change the impeller and noticed 3 of the fins were sheared off. I went to remove the impeller and it wouldn't budge. I looked closer at it and noticed it had spun on the shaft and was no longer in alignment with the retaining key. Does anyone know how this could happen? I looked at the key itself, once I got the impeller off, and it does look a bit rounded but looks like a perfect fit to both the shaft and the impeller. Is this normal? Lastly, does anyone know where I can get a replacement retaining key? I think I would like to replace the key also, being that I'm already in there. Any help on this would be greatly appreciated! Thanks in advance.

 

[Yepblaze]

Re: Impeller change problem...1964 Merc 50hp

The key comes with the pump kit you get from mercury, or available separately.

Not unusual to appear a bit strange when first viewed.

Sometimes a short round rod is used as a key, and sometimes it's a flat curved humped thing. Either way they bot work equally well.

 

[prolinews]

Re: Impeller change problem...1964 Merc 50hp

As far as the water pump being spun out of alignment I've done it pumping louisiana silt through the motor. I hope the tips that were sheared off don't cause you any problems . I am not familar with a 64 merc but on other models I've been able to attach a hose to the water tube pull the t-stats and flush pieces out . If it doesn't run hot I wouldn't worry about . If so buy some gaskets and start wrenching.

 

[Cpt.Justice]

Re: Impeller change problem...1964 Merc 50hp

Yepblaze...mine appears to be the short round rod type. If it comes with the pump kit that will be great, as I am going to have to get one, I destroyed a gasket in the process of taking off the impeller. Thanks for all your info!

Prolinews...Fortunately, I found all three tips just sitting in the bottom of the pump and was able to get them out with no problems. Thanks for your help!