Lower unit leakage

[rjoynt]

I am in the process of fixing a 6hp Johnson that had a huge crack in the skeg. I thought that it was from damage from hitting something, but a good and wise friend of mine pointed out that it was due to water freezing and cracking the skeg. Since he was the one that was going to weld it, I of course agreed with him. And because he is more experienced than I.
So, it got me thinking. Does water get in and push the gear lube out, or does the lube get forced out and get replaced by water?
And, is it true that you should not put a different skeg on it, that somehow they are matched?
Thanks in advance.
Bob

[foot_doctor]

The water pump resides above the gear case, and is seperated from it by a seal surrounding the drive shaft. When the seal fails, the pump pressurises the case, and forces the lube out. That’s why we drain and lube our cases before we store them for the winter. Lots of fine outboards have been disposed of in our state, Wisconsin, merely because the gear case cracked from water intrusion.. Too bad. R.T.

[frankr]

True, skegs are matched and not to be interchanged. But we all know it has been done anyway. Might be successful,might not.

[outbdnut2]

I’ve had propeller repair shops weld them up at reasonable cost.
Dave

[fleetwin]

Your pal is right, the cracked skeg is most likely due to freeze damage. There was water in your gearcase, it froze during the winter and split the skeg open. Like Frank says, the skeg and upper gearcase housings are a matched pair and should not be interchanged. But, many people do it all the time, and I’m sure it probably wouldn’t make much difference on this small engine.
Sounds like your friend will be able to weld the skeg crack, so give it a try. The problem is that you will need to find out why the gearcase was leaking to begin with, and make sure the weld is water tight. While the gearcase is all apart, it would be advisable to replace all the seals and orings which usually requires some special tools. You will need to inspect all the shafts and castings to be sure there are no imperfections/wear that will cause water leakage. Once the gearcase is reassembled, the only way to be sure it does not leak is with a pressure tester.
Again, there was water in your gearcase which froze during the winter causing the skeg to split open. Once everything is reassembled, it is a good idea to change your gearlube frequently to ensure there are no water leaks…
The original leakage issue allowed gear lube to leak out of the gearcase, it was replaced by water….

[The Boat House]

Every fall you need to change the furnace filter, rake up the leaves,
test run the snow blower, and when you take a motor out of the
water for the last time, change the oil in the lower unit. Every motor.
Every year. It’s like remembering birthdays and anniversary. Life is so
much easier when you do.

[rjoynt]

Update:
Gary did a great job welding the crack. Put it together and the shift shaft seal leaked. Replaced the seal. The leak was then through the drive shaft seal. Replaced the seal. Then the leak went to the gasket under the plate that the stainless plate below the impeller leaked. Then the weld is leaking out at the beginning of the weld, a very small pin hole. Rather than rewelding, any suggestions on how to plug that leak? JB or something?
This lower unit is by far the worst that I have ever seen!!!

[The Boat House]

• This reply was modified 5 years, 5 months ago by The Boat House.
• This reply was modified 3 years, 2 months ago by The Boat House.
• This reply was modified 3 years, 2 months ago by The Boat House.

[fleetwin]

Yeah, I was afraid of the weld itself leaking. At this point, I would just coat that weld with JB weld…
Then be sure to change gear lube often. There are no actual bearings in this gearcase, so I would not worry about it too much.

[garry-in-michigan]

But there are actual bearings. They are made of phosphor bronze and won’t rust, but still need lubrication. JB Weld requires a rough surface that is totally clean. GOOD LUCK . . . 😎

[Author]

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