1967 100HP Johnson

[nolanb]

Re: 1967 100HP Johnson

Got the lower unit off! and now starts the real reason I wanted to get it off... I've been having oil come out the water intake pipe after I run the motor. When i tilt it up out of the water, and drop in back into the down position oil drips/runs out the water intake. Any advice on where I should start my search for repairs to fix this problem? I think I'll be set to take it out on the water and have a good time once I get this fixed. Thanks

 

[Joe Reeves]

Re: 1967 100HP Johnson

When i tilt it up out of the water, and drop in back into the down position oil drips/runs out the water intake.

Normally that's due to the top driveshaft seal in the lower unit (just under the water pump). However, check the appearance of the oil you see dripping against the gearcase oil just in case the unburnt fuel/oil mixture may somehow be gaining access to that intake.

Actually there shouldn't be any way the unburnt fuel/oil mixture could get to that intake screen but weird things happen. You're going to dismantle the water pump anyway so you'll have a good view of the gearcase seal.

 

[nolanb]

Re: 1967 100HP Johnson

Its definitely coming from the gear case. I have the impeller housing off and when I removed it there didn't seam to be any gasket there. Should there be a gasket there somewhere? And I don't quite understanding how the gear oil is getting up to there anyway because shouldn't all the gear oil be down in the lower unit and not in the gearcase extension? Or does the oil have to come up along the crankshaft and I'm missing the gasket I should have there?

 

[nolanb]

Re: 1967 100HP Johnson

I have taken the impeller wear plate off now and the gasket underneath the wear plate was destroyed, and there was a pretty fair amount of gear case oil sitting in the recession under the gasket. So I believe I now have to remove the bushing that goes around the driveshaft and replace it and get a new gasket. (Still unsure if there should be a gasket on the top side of the wear plate?) Can anyone show me where to find a lower unit seal kit for this motor because im having absolutely no luck. Thanks!