Old johnson leaking LU oil

[.jj.]

I have an older Johnson 10 horsepower motor I got used last year. I noticed it leaking lower unit oil this spring some and now at the end of the year it's leaking probably double what it did before. I changed the oil in the middle of summer and it was milky like it had water in it. From my research it sounds like I need to change the seals? How hard would this be to do myself? Also the motor also has two holes in the LU that appear to have oil coming out of. Are their supposed to be drain holes or something like that in it? The top hole is above the top vent screw that I fill the LU oil to, so I'm confused why LU oil could come out of that? This is my first boat so I'm trying to learn all I can thanks for the help! Pictures of the two holes i'm curious about.

 

[racerone]

There are drain holes and often an oily residue will leak from them.---This leakage is alarming to some novice owners , but is normal.-----No special tools required to change lower unit seals except for the shift rod bushing and O-ring in there.---That o-ring can be changed without removing the bushing.---Most folks prefer to drive the bushing out with a right size rod of some sort.-----Factory had a special tool for that or you can run a 5/16" tap in there to pull it out.------I have used all 3 methods and no problems.

 

[Vic.S]

You dont specify the age or give the model number but,

As said drain holes . You would normally expect to see some unburnt oil from the fuel leaking from them, but not LU oil

Read http://forums.iboats.com/forum/engin...nit-by-iwombat

If you have water entering the gear case you may have to consider replacing the seals and/or the gearcase head.... the latter is expensive though

 

[HighTrim]

It is a 2 stroke right. Not all of the fuel/oil mixture gets burned. This unburned mix gets shot out of the exhaust with the spent cooling water. The gooey mess you see coming from the drain holes after you run it and pull it out of the water is just this.

THe gearcase has cavities in it, and if there were no drain hole, the sitting water would freeze in the winter, and crack the gearcase.

I would buy a whole seal kit, about 20 bucks. You will also need some 3m 847, which will cost you more than the seal kit. It works well though. If you do it, I can send some literature on this.

I have a tool to remove the shift rod bushing. Basically, a 5/16" rod ground down to 1/4", over about 2". FR on this forum used to make a tool, which works superbly, but don't think he has any left. As stated, you could tap the bushing and use a puller to pull it out. I have never tried removing the o ring without removing the bushing, but imagine that would be quite difficult! Would have to see that done. Don't think I could do it without plucking out my eye balls, lol. How about getting it back in there? Not doubting you racerone, just would think that would be near impossible.

 

[boobie]

Pressure test it before taking it apart so you know exactly where it's leaking.

 

[racerone]

Nothing to it really, just some pateince and old time " know how " and you can remove and install that O-ring without removing the bushing.

 

[nwcove]

Nothing to it really, just some pateince and old time " know how " and you can remove and install that O-ring without removing the bushing.

not doubting either......but that info would be great to share! ive removed a few of those bushings that made me cringe because they were somewhat stuck....skipping the pulling step would be nice!

 

[HighTrim]

Ill try it tomorrow. Maybe possible. I can see possibly getting it out with dental picks, but getting it in? Not sure. The bushing compresses the o ring, so not sure how that can be done. I do it in about a minute with a good tool, so don't think I will ever try other than for experiments sake.

 

[boobie]

The dental pick is the secret for getting them out and re-installing. I've done a lot of them that way.