1990 mercruiser 4.3 outdrive leak alpha one gen 1

[Rinker captiva 206]

I have gear case fluid leaking from the water hole on the bottom of the drive. Took the gear housing off and it looks like oil is coming from the upper driveshaft where the driveshaft goes into. What tools and how hard is it to replace the seals in the driveshaft housing? Thanks in advance

 

[Bt Doctur]

Do you mean the lower units driveshaft where it goes into the upper unit?
http://www.boatfix.com/merc/Servmanl/6/6A3R3.PDF

 

[Bt Doctur]

http://www.boatfix.com/merc/Servmanl/6/6B3R3.PDF

 

[Rinker captiva 206]

I believe it is number 13 on the diagram. Number 14 fell apart and pulled it put from the bottom. But I believe there should not be gear lube where the driveshaft splines go into upper housing. Correct?

 

[Bt Doctur]

#13 is the seal to keep water out of the shaft area, #14 is the actual oil seal

 

[achris]

You need the special spanner to remove the front cover from the drive (sold right here on iboats) and a 12 point 3/8" socket to remove the top cover screws.

Remove the front cover, pull the drive gear and bearing assembly out (don't lose the shims!), remove the top cover and lift the driven gear and upper drive shaft out. You now have access to the seal. Replace it. Drop the upper drive shaft back in. Put the top cover back on (with a new 'O' ring) and torque the screws to 20ft-lb. With the shims in place, slide the bearing and drive gear assembly back in, turning slightly to ensure the gears mesh. Put the cover nut back on and torque to 200ft-lb.

Easy. But check the seal surface on the bottom of the driven gear, you may need to speedie-sleeve it.

Chris. ...

 

[Rinker captiva 206]

Thank you guys for the help. I am gonna try to get that apart and back together today. I will post more if I run into trouble.