Odd grey discharge from lower part of 1962 Johnson 10hp Seahorse

[rdecosta]

https://www.youtube.com/watch?v=VOsEkNKQJc0

I had been trolling for about an hour when it stalled. It started doing this when I tried to start it again.

Specs:
1962 Johnson 10hp Seahorse
Recently resealed the lower unit, cleaned the carb, new water pump impeller
Regular gas
24:1 oil mix

Cheers,
Richard deCosta
Two-Sheds Fishing Guide Service
http://guide.richarddecosta.com

[dan-in-tn]

The motor appears to be running rich. Before just trying to tune it leaner with the low speed needle I would check the thermostat to see that it is operating properly. At proper temp this motor should reach approximately 135 degrees at idle. The closer to this you can get the leaner you can run the engine and the less emissions left to go in the water. You might want to look at reference #26 on ME #308506 oil return hose to be sure it is not kinked or clogged. This keeps the heavy ends of unburnt fuel moving until the next time you run wide open and burn it up. There is a hard line from top main to bottom that needs to be open also.
You might also check your sync & lync to see where your carb is picking up the mag plate. I set my needles where they are straight up & down. When starting a cold engine I back the low speed out a 1/4 turn until the motor warms up. Then put it back into its original position. If at anytime it won’t idle properly there then I know something is amiss. I usually start with temperature on a thermostat controlled engine.
Synthetic lubes or biodegradeble oil will help & I think this engine can run on less than 24/1. It has bearings on wrist pins, but maybe not center main? Someone will be along to confirm. Hope that helps!

Dan in TN

[rdecosta]

I did initially have the mixtures too rich, no question. I returned them to the middle setting and things seem to have cleared somewhat.

Everywhere I’ve looked has said that the oil ratio should be 24:1, as per the manual, but all evidence suggests this is much to much oil.

I need to find a shop manual to comprehend all the parts in your reply. 🙂 Thanks!

[crosbyman]

have you tried boatinfo.com

http://boatinfo.no/lib/evinrude/manuals … de.html#/0

this one is older but contains lots of info you can use
http://boatinfo.no/lib/johnson/manuals/ … on.html#/0

Joining AOMCI has priviledges 🙂

[lindy46]

Well, I’ve had many pre-1964 Johnnyrudes running 24:1 that have done the same thing. I’ve always considered it normal. Most that unburnt oil that you mix with the gas ends up going out the exhaust. Give it a good high speed run after trolling – that will help.

[amuller]

emulsified oil/water mix? Try it out as mayonnaise.

Seriously, debates about acceptable fuel mixes for old outboards go on forever–they simply have no endpoint. Even OMC itself screwed up repeatedly on this subject. Many people would feel that a powerhead with all rolling element bearings should be able to run at 50-1, but there may be other considerations such as the surface finish of the pistons, management of liquids in the crankcase, etc.

I have a 1965 5.5 and run it at 24-1 because it (probably) has plain bearings (bushings) on the wrist pins and the center main is also a plain bearing. If the parts listings on Marinengine.com are correct it looks like your 1962 10 hp has needle bearings on the wrist pins but plain big-end bearings as well as the center bearing. If that is the case I would run it at 24-1 also. This was a transitional period for OMC and they did advise 50-1 for some plain bearing engines such as the 3-4 hp. But this engine is very small and probably has very low bearing pressures. All in all, not a simple subject.

[amuller]

Correction: I’m advised that the ’62 ten hp does have needle bearing big ends. This makes better sense than otherwise.

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