Mercruiser Alpha 1 Gen 1 water pump service

[Donald]

I have the lower unit pulled to replace the impeller. I found a YouTube video on doing the impeller and it suggested to forget the o-ring near the top of the shaft going to the upper unit. Apparently the shaft goes into a seal you end up not being able to set it properly into the seal if you use the o-ring ring.

In the Gen 2, there is no slot for an o-ring.

 

[DoubleWasp]

Yes. That ring does make it a bit of a dastard to get in there correctly and efficiently. Just leave it out.

Most of the A1G1's we service have long since had them left out.