Water pump replacement -dumb questions

[BuzzM]

I will be changing the lower unit impeller on my 1982 Mercruiser GM 5.7 with a pre-alpha.
1. Can this be accomplished correctly without removing the outdrive?
2. If I have to R&R the outdrive, must I replace the gasket kit for the outdrive each time? Do I use gasket sealer when I do so?
It is a pain to get it from the marina to my house, so I'd like to do this at the marina yard as quickly & simply as possible. It is not overheating but , it has been almost 2 years since replaced professionally.
I have replaced impellers on evinrude outboards before.
Mechanics are scarce here.

 

[Don S]

Re: Water pump replacement -dumb questions

1. Can this be accomplished correctly without removing the outdrive?

Yes, it can, but it's easier with the drive off. But you really need to pull the drive, lube the ujoints, gimbal bearing, lube the splines on the input shaft (A MUST) and check the alignment at least yearly.
Why not do it all at the same time.

2. If I have to R&R the outdrive, must I replace the gasket kit for the outdrive each time? Do I use gasket sealer when I do so?

Absolutely. gaskets and seals are a ONE time use item. There is also orings on the input shaft, a large diameter ring around the inside of the bellhousing, and a ring around.