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1955 Johnson 5.5 Seahorse rebuilt and runs but not well....

Lee B

New member
Went through the entire motor. Compression was decent and equal. Changed coils, points, condensers, pug wires. Points are gapped well, .020 gauge goes, .022 will not. Thorough carb rebuild. I left out the sintered metal filter and put paper filter inline from tank. New float set nearly flat, just slightly uphill. Champion plugs J8C gapped .030. Running non ethanol gas with Johnson/Evinrude mix oil at about a 20:1 ratio.

I have read the needle adjustment procedure and understand it but it just doesn't work as advertised for me. I can get it started easily enough and can keep it running. I can get a smooth running lower rpm range by nearly closing the high speed needle but it obviously starves when you try to rev it. If I open up the high needle a bit it runs roughly and hardly idles at all but will rev up (roughly). The low needle doesn't seem to do much at all. If I crack the choke again after its warm things seem to improve but still not great.

This is my fathers motor and he got it in the 60's. I would be surprised if this motor has more than 50 hours on it. Its in really amazing condition. Will try to figure out how to put pics on here. It hadn't been started in more than 50 years. Im trying to bring it back to life and almost there but, something I did wrong, or I overlooked.

I found a 1967 14ft Starcraft aluminum V to put it on.
Looking forward to fishing with my Dad if I can get the motor happy.
I would really appreciate any info or ideas you think might help me, Lee.
 
Did you replace the float? Sounds like it is running rich possible fuel soaked cork float? Pull the float and let it thoroughly dry after you clean it with carb cleaner then dip it in a cup of clear fuel proof model airplane dope. If you put finger pressure on the float the needle is probably damaged. Instal a new needle and seat with the copper washer. Hold the carb upside down and check the float is level with the bowl and not cocked side to side. If you have to adjust it pull the float put and bend the bracket never put finger pressure on the float. Preset the slw needle out 1 1/2 turns and the high speed 3/4 turn. Then follow the needle adjustments set the slow needle for a smooth idle in forward gear in the water then point it at the big part of the lake and go WOT and adjust the hogh speed jet for the best performance. Run it at least 10 minutes at high speed the go back to idle and adjust it again. Once set you should not have to touch the needles until the next carb rebuild.
 
Thank you kimcrwbr1 !
I did put a new float and needle and seat and yes set it level with float bowl. And yes, i did put finger pressure on it. )-:
Is it really that sensitive? Thanks for the help!
Lee.
 
Get a new flange gasket and lightly surface the flange on the carb. On a glass table with 220 grit pull the carb in one direction only until it all shines the same. Once you mount the carb double check it is in sync with the spark advance.
 
No it was the white nylon gasket/washer. Its what came with the rebuild kit.
Thank you very much for the reply and help! Not sure where to get the copper washer. Here at marineengine?
Lee
 
There is a mark on the throttle cam on the points plate the carb should just begin to open as that mark passes center of the roller. I believe you loosen the two bolts for the cam and adjust the cam position to make that happen.
 
You can get the sync exact with a alligator clip and a straightened paperclip. Clip it on the throttle butterfly shaft and watch the mark and roller the wire should just begin to move as the line passes center of the roller
 
Does your flywheel have the access hole on the flywheel for the points? You can also get timing exact with a timing light. Point the light at the two marks on the side of the points plate. The single mark on the flywheel should be in between the two marks on the plate. adjust the point gap to make that happen there are two marks on the flywheel 180 degrees out one for each cylinder.
 
kimcrwbr1 ! Thank you very much for your time and knowledge! I did everything you said and one of them fixed me. It idles very well and revs up nicely in a barrel. Ready for open water fine tuning now! Thank you again, Lee.
 
Are the packing nuts snug so it it difficult to turn the needles with your fingers? Set the slow needle after the engine is fully warmed up about five minutes the take it WOT and adjust the high speed jet for the best performance. Run it hard for 10 minutes then go back to idle in gear and fine tune the slow needle. You should not have to adjust them again until the next carb rebuild.
 
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