50 hp Force water pump change question

[Basstrackerpro17]

I dropped the lower unit on my 1990 Force model 507F90C 50HP motor to change the water pump impeller. I found a piece of rubber, like some kind of rubber seal or boot torn in half just laying in there that I have no idea where it came from. The only two places I think it might could come from is at the top of the tube that slides down in the water pump or maybe at the top of the drive shaft that goes back into the top of the motor when you slide it back together. Does anybody have any idea where this rubber seal might go? Thanks.

 

[TwoFish]

Re: 50 hp Force water pump change question

Probably parts number 1 or 2. They act as a seal on top of the driveshalt to prevent water getting into the spline where the driveshaft fits into the power head. Mine fall out every time I drop the gearbox. If you only have one of them you may want to get a torch and look up the leg as they often get stuck on the way out.

http://www.crowleymarine.com/mercury-outboard/parts/1326_160.cfm

Only other part I can think of is the water tube seal that fits between the water pump and the water tube that leads up to the power head. This part has a nylon outer and a rubber centre section that acts as a seal. Not as likely to be this as you would be having cooling problems it this part was that badly deteriorated.

 

[Spundo]

How important is the upper seal? The rubber of mine separated for the metal ring. Thank you for your response.