If the shaft or shafts have a groove cut in them where the old seal was don`t press the new seals all the way in leave them out 1/32 inch so the seal
Funny, I have the same issue with my 1972 7.5 Mercury Thunderbolt Serial# 3281871 -- bogs down at high speed - runs fine at low speed.
I'm in the process of rebuilding a Johnson 1966 20hp FD-20 and noticed the other day there are some small holes in my lower unit, one is leaking a little
O.k. guys. I did a vacuum test last night. I have the impellor off and when I pull a vacuum, it is sucking air in around the drive shaft seal. Is that