Below water opening to drive shaft tube. Evinrude 75 HP 1961 Mod.# 50525

[Lostuzer]

As I?m reassembling I notice a hole that opens up in the tube that encases the drive shaft. I assume that this hole is to drain water that might have found another way into this cavity and should not be plugged. Am I correct or am I missing a check valve or something?

Any insight will be appreciated,
Bob

 

[F_R]

Re: Below water opening to drive shaft tube. Evinrude 75 HP 1961 Mod.# 50525

You are correct, it is a drain hole and should not be plugged. Any water that escapes from the water pump, through the drive shaft hole, enters that tube. If there were no drain, that water would fill the tube to the top and that's where the lower crankshaft main bearing seal is located. You do NOT want water being forced up through that seal, believe me. Actually there is a similar hole, higher up, for short shaft situations, and a vent hole at the top. You do not want to plug any of them...or any other drain holes for that matter.

 

[Lostuzer]

Re: Below water opening to drive shaft tube. Evinrude 75 HP 1961 Mod.# 50525

Thank you again F_R for great advise and the reasoning behind it.

Sincerely,
Bob