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Water in lower unit

Ole1010

New member
I was putting my boat away for the winter yesterday and when I went to change the lower unit oil there was quite a bit of water and the oil was just like chocolate milk. I have done some reading and it said to do a pressure test. Is that as easy as putting a valve stem in one spot where you drain the oil and a gauge in the vent hole? Any help would be appreciated. Thanks
 
I made an adapter like that that screws into the lower drain hole.-----Uses a brass valve stem.----I use a hand pump for total control of pressure.-----Many motors use a 3/8-NC thread.-----Sounds like a seal kit in in the future.
 
Where did you put your gage? Just in line with the valve stem or in the vent hole? And I also read that it could maybe be the prop seal? With a seal kit will that just be lower unit seals? Is that something I can just do myself?
 
What motor do you have.----My adapter screws in the drain hole and has the air valve and gauge on it.----But you can separate the 2 if that is what you like.-----Seal kits are offered for just lower units.-----At 5000 rpm the rubber lips on the seals do wear out over time.----That becomes an issue in colder waters !
 
This site here does not show an assembled kit.------You would order the seals individually.----Do not forget the shift rod o-ring.---Critical seal but often overlooked.
 
Call Tim's Outboard, Hackensack MN. They are the very best for clean used or new parts 218 682 2331. Tell 'em Tim sent ya. The o ring for shift shaft is harder to change, I have a trick that makes it real easy. Is there fishing line on the prop shaft? Do you tow the boat while it is in neutral? Not smart.......Why? The prop spins and damages the outer seal which is supposed to be lubed and cooled with water. For testing with pressure, what I made is an adapter that fits on my Stant radiator tester. I COMPLETELY drain all lube/water out of unit, then put in the upper plug/vent screw. Add about 15 psi with my radiator tester which has a small hand pump. Then I check with soapy water if it won't hold pressure while I wiggle and turn shafts, move shift rod, well you get the idea. You can't effectively directly see the leaking air around the imput shaft because of the water pump is in the way. So if you are loosing pressure and the other areas are not showing a leak, you have to suspect the imput shaft seal, or bearing retainer housing seal.
 
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Yes I do tow it on neutral, I always shut the motor off in neutral, dont known why just always have. What do you mean lined by water? I found a gasket kit on this website I tried to attach a picture of it but it won't let me 0396355 gear case seal kit. Is that everything I would need? No there's no fish in ng line stuck in it at all. I'm going to do a pressure test on it this weekend when I have time. What's the trick for chang in ng the o ring?
 
Yes I do tow it on neutral, I always shut the motor off in neutral, dont known why just always have. What do you mean lined by water? I found a gasket kit on this website I tried to attach a picture of it but it won't let me 0396355 gear case seal kit. Is that everything I would need? No there's no fish in ng line stuck in it at all. I'm going to do a pressure test on it this weekend when I have time. What's the trick for chang in ng the o ring?
 
Spell correct bit me on that one again. Its supposed to read "lubed"....I already edited the post, So check it again.
To change o ring you can take out the o ring sleeve with a punch, just the right size so it barely fits through the shift rod hole in the aluminum housing, but it will NOT fit through the little retaining sleeve. Therefore you can tap out the sleeve with the punch. For assembly I have learned to first lube things up, then get that fat o ring into the aluminum housing. Next just "start" the sleeve into place, but before tapping it all the way down with your pipe or deep socket.......put the shift rod in from the other direction, making sure there are no burrs on it from prior work or disassembly. Get the rod so it sticks through the o ring and completely through the sleeve.....it will have entered your pipe or socket slightly. Then tap down your sleeve and checking shift shaft friction as your going, got the o ring pressed snuggly in place and providing lite to moderate friction So you feel it when moving the shift shaft up and down. This friction is really what insures a proper seal from o ring to shaft. In other words the o ring will be slightly expanded as it is squished by the sleeve.
 
Ok I will definitely be reading this again when it comes to that point. Did you see the number for that seal kit I put on there? Would that be what I'm looking for?
 
Most prop shaft seals are installed back to back.....why? Because the lip side is the primary and most effective seal. So, the inner seal lip is facing and working in the oil and the outer seal lip is facing and working in the water. So without water to quench the outer seal, the lip gets damaged/melted/brittle.....etc. Then the water can get to the inner seal which has very little tolerance from that direction. These are primarily a "directional" seal. Outboards with a single seal are slightly less effective, however many seal designs.....even single, really have a secondary surface or lip that needs lube from the water. So.......DONT TOW YOUR BOAT WITH TRANSMISSION IN NEUTRAL, brother.......pass it on!
 
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