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1973 25 HP Johnson

D

Dan P

New member
I have a 1973 25 HP Johnson that belonged to my dad that I just got from my brother. I changed the lower fluid last week and when I run the motor there is a lot smoke coming from the lower unit at high speed. When I stopped the motor and I noticed that there was a lot of milky oil in the garbage can that I used to run the motor in. I pulled the motor out of the water saw milky oil running from a hole just below the fill mark on the lower unit. Motor ran fine with plenty of water going through. What should I do next?:)
 
open the fill hole on the motor, see if water comes out, if so you have seals leaking. if not most likely exhaust oil.
 
I removed the fill cap and a light yellow fluid came out. Looks like no water. I just changed the lower unit oil and ran twice since in a barrell. Again, lots of smoke when running at high speed. Should the oil be that color with only running for a total of 30 minutes.
 
No, so you have a seal problem with lower unit. Exhaust smoke and discharge would be normal with a "barrel run" of a long stored motor. Remove the prop first and take the fishing line off the shaft, if any. Examine the seal and if it had fishing line for some time it could have damaged it. The seal under the water pump is also a likely suspect.
 
I'll try that tonight. I assume if the oil is the color light creamy yellow that is indicates that water is getting in. Is is normal that much discharge drains out of the little holes just under where the lower unit connects. It stopped once I shut off the motor.
 
what 2 stroke oil ratio you running? should be 50:1

sounds like you need to do a "decarb" of that motor with some seafoam.

lots of instructions on google....

here's one fairly typical:
http://www.switchbait.com/forums/showthread.php?t=159

welcome to the 22CID Johnnyrude world... great motors- I have 3

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I pulled the propeller and found no fishing line. I drained the lower unit and let drain all day and then added new fluid and ran the motor at all different speeds and forward and reverse. A little discharge of a white milky oil coming out of a little drain hole. I removed lower screw to check fluid and it was again the color of cream corn. I assume water is getting in and causing the yellow color. Can I run with color, if I new I just changed it.

Thanks,
Dan
 
lower unit oil always looks creamy after a run. you need to let it sit for a day and then open the drain screw. If there was water, you'll know because ALL of the water will drain before any gear lube.

I thought your issue was sludge out the exhaust?
that has nothing to do with lower unit gear lube.

smoke and milky water in the barrel is from the 2 stroke oil mixed in the gas. that's why i was linking you to decarb instructions.
 
thanks, I'll check it tonight. I was talking to my brother who has owned several boats and he told me the gas they sell in Oregon has a lot ethanol in it and that I should go get some stay-ble to put into the gas tank to help the gas.
 
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