1979 Mercury Lower Unit Help

[Wide_N]

Part # 15 in the picture is an o ring. Can someone tell me exactly how it will go? Will it go at the bottom of the base or fit over the bottom of the base?

 

[GA_Boater]

The base has a groove the O-ring fits into.

 

[Chris1956]

Make sure you choose the correct one for your waterpump base. Rebuild kits usually have several to choose from. The one that fits the snuggest in the groove and will allow installation into the gearcase casting is the correct one. Obviously clean and grease the driveshaft, oring and driveshaft seal.

 

[Wide_N]

Got er done and all seems good.