water pump replacement - new base doesn't fit?

[Lbicher]

Hello,

I have a new project which has a Mercruiser 3.7 Liter and an Alpha 1 outdrive. I am replacing the water pump and picked up the GLM kit #12120. When I go to put the base on, it doesn't want to fit properly. It looks as though the part of the base with the large o-ring is just a hair too big to go into the cavity at the bottom of the driveshaft. Has anyone else had this type of issue or does this need s bit of force to get this part installed? Unfortunately, I picked up the project after the drive was already separated and the old water pump was removed so I do not have the original part to compare with.

Thanks in advance for any help you can give.

 

[FreeBeeTony]

What year is the outdrive?
​Does the vertical shaft on the lower unit have a pre-load pin? If so you may have the wrong kit.

 

[Bt Doctur]

if the lower driveshaft has a small pin sticking up, you have the wrong base. Everything else in the kit will be fine
base 18-4317 46-57234A1

 

[FreeBeeTony]

What year is the outdrive?
​Does the vertical shaft on the lower unit have a pre-load pin? If so you may have the wrong kit.

Looking for verification of my adivce given BtDr........was I on track?