Posted by BC_Montauk_17 on 03/26/13 - 10:24 AM
#1
My 1990 Yamaha 90ETD appears to be leaking oil from the water intake area. Before I take the boat to a marine mechanic, I was wondering if anyone on the forum can shed some light as to what may be wrong.
I have uploaded a photo of the gearbox / oil leak on my personal page. Any constructive input will be much appreciated.
Posted by Jeff on 03/26/13 - 10:52 AM
#2
For oil to be leaking out like that, I would have to assume your gear case has a crack in it. Do you live in a part of the World that sees winter temps below freezing?
Posted by BC_Montauk_17 on 03/26/13 - 10:57 AM
#3
I live in the Greater Vancouver area of BC, Canada. When I drained the oil from the gearbox this Spring, there was an excessive amount of water found within the gearbox. I had previously changed the oil last Summer (when I took possession of the boat) and had ran the boat for the 2012 boating season. I had neglected to change the oil before storing it outside for the Winter.
Posted by Derwd24 on 03/26/13 - 12:30 PM
#4
You may just have bad seals in the drive shaft housing (right below the water pump). Pretty easy fix.
Just looked up the parts on Boats.net, there's 2 seals, a bearing and a shim washer. When you disassemble, inspect the bearing and shim for rust as water infiltration there may show. Not sure how the drive shaft is on a Yamaha, but best to replace the bearing while you're in there anyway if you can...
When you remove the lower unit and pull the water pump, you can pressurize the gearcase and use soapy water to spot the leak.
Edited by Derwd24 on 03/26/13 - 12:37 PM