9.8 lower unit seals

[James Schmidt]

I have a 1985 merc 9.8 hp that seems to be leaking oil around the prop shaft. Can I replace this seal without dropping the lower unit? It also looks like you need a special wrench to remove the nut that holds the housing.

James

 

[Laddies]

Re: 9.8 lower unit seals

Yes, it's not a problem, the problem is getting the retainer nut out witthout a spanner

 

[diaric]

Re: 9.8 lower unit seals

before you go and rip it all down, make sure its the prop seal leaking. 1st decide if its the gear lube leaking or just oil from exhaust. 2nd the seals under the waterpump are more prone to leak, and comes out through the prop as exhaust water would.doing a pressure test on the lower unit would tell you exactly where.

 

[James Schmidt]

Re: 9.8 lower unit seals

It is lower unit oil seeping because I just changed it and it is new oil. What is the best way to pressure check the lower unit.

 

[diaric]

Re: 9.8 lower unit seals

you can pressure test with no more than 5 psi. some stick the nozzle of a blow gun in fill hole and give a squirt. i've connected lube pump to filler hole, levt vent in, and given a couple gentle pumps. listened to where it leaked, or if lower unit off will see come out under water pump or hear out prop seal