Hm okay, I don’t think I see how this small O-Ring could seal the pressure of a crankcase. Anyway to determine if that’s the case for my engine?
Any body have thoughts about dremeling the splines ?
Thanks for the reply, Scott. I'm actually not sure what engine this lower unit came off of, but it was advertised as fitting 7.5/9.8s. The guy assured me that since all the lengths of the rods are the same, it should fit.
Hello all!
I have a 1984 Mercury 9.8 that had enough issues with the lower unit that I figured it would be cheaper and easier to swap out the whole unit. I found a used one locally at a Mercury dealer that was a bit newer. The original bad one has an O-ring below the splines on the drive shaft...