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Oil leaking from holes in lower unit, 84 johnson

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alexstuber

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Hello, i just started my 1984 25 hp johnson up today to make sure it was ready for duck season. I idled it for about 10 minutes, and after shutting off noticed oil running out two small holes in the lower unit. Does this indicate that i need new seals? Thanks for your help!
 
Question gets asked almost every day. You put oil in the gas. Guess where that oil goes. Some burns (smoke) and the rest goes out the exhaust for you to look at and panic. But check your gear oil for water intrusion just to be on the safe side.
 
At first i thought it was unburnt oil, but it is not coming from the exhaust ports. It is coming from several 1/8 inch holes in the side of the lower unit. Im trying to post a picture but it wont let me.
 
Correct-----And you will see oil draining out of those small holes.----Usually it is the oil that was mixed with the gas !!----Most but not all the exhaust goes out the snout behind the prop !-----Time to visit a shop with a gray haired mechanic who can explain this issue you have.
 
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alexstuber said:
Well, ill go ahead and check the gear oil and go from there.
Click to expand...
Outboards have one operating feature different from most 2-strokes.
That is, the exhaust pipe is a couple feet underwater. That water column creates pressure, which impedes the free flow of exhaust. This resistance could be overcome by running the motor at a higher rpm, but then it would not troll at the desired slow speeds, as idle rpm would have to be high.
Manufacturers solved this by placing some small exhaust ports up high, generally just below the cowling. Thus allows exhaust to escape freely at low rpm.
As stated by the gator & Racer, 2-strokes never burn all of the fuel or oil that goes through them. This partially burned hydro-carbon creates blackish gunk, which eventually leaks out, wherever it can.
You don’t need to look at the gear oil for your issue, it has nothing to do with what you are seeing. You need to go to Leroy’s Ramblings, (Google it), & gain a better understanding of how these motors work. You will discover A), how exhaust is routed through the lower leg.
B) the two small holes do drain water.
C), they often weep gunk, especially if the motor is used at low speed for extensive periods, or run rich.
D), look just below the last post in the thread, you will find dozens of threads questioning gunk leaking From small holes in the leg.
http://www.marineengine.com/boat-fo...483-Oil-coming-from-small-holes-in-lower-unit
This shows it graphically, if you’re in a hurry, scroll down to about 2/3 way.
https://leeroysramblings.com/Johnson 9.9_15.htm
 
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Agreed. And there's nothing wrong with grey hair . Men age like wine.

OP is running too rich. Trolling too slow. Or his thermostat is stuck in open. Bottom line , you're not buring efficiently. And a little gunk is completely normal.
 
Also, any advice on how to operate the manual primer on my outboard? Do i just pull it out when starting, and then push it in when started?
 
I think that is a pump.----You pull it out.---Push it in.----Pull it out. ----Push it in.----Then out half way.----Pull the starter cord.----Push it in after motor warms a bit.
 
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