1955 , 5.5 hp Johnson ,need little help

[aaind]

Runs great on the top end ,but low idle is poor ,go into a 4 cyl mode ,but the very slightest twist up the throttle its back to 2 cyl ,but still cuts out and back to ,I dont think its a gas problem ??

Please give me all your thoughts

 

[Daviet]

Re: 1955 , 5.5 hp Johnson ,need little help

What do you mean by 4 cyl mode?
Have you checked the spark, does it jump a 1/4" gap and is it bright blue?
Is the low speed needle set correctly?

 

[F_R]

Re: 1955 , 5.5 hp Johnson ,need little help

Are you saying one cylinder cuts out at idle? Check the spark plug wires for arcing through and continuity. Check the coils. Did you replace them, or has somebody else replaced them? There are no original coils that are any good in those 1955 motors. And of course, the obvious still counts, points, condensers & plugs.

 

[1946Zephyr]

Re: 1955 , 5.5 hp Johnson ,need little help

Yep, I second that. I would go through the entire ignition system and refurbish it. Once you do, it should run like a cut cat.
Also, a good reference on your needles is 1 1/2 turns out, from gently seated on your low speed and 3/4 turn out from gently seated on your high speed. Take it to the lake and fine tune the adjustments. I have found on those old 5.5's, the high speed likes to run at around a half turn out and the low speed, about 1 1/4 turns out. Make small adjustments and allow a few seconds of run time, to let the motor react to the adjustment.
Excellent motor you have. I own 4 of the of 5.5's

 

[aaind]

Re: 1955 , 5.5 hp Johnson ,need little help

Yep, I second that. I would go through the entire ignition system and refurbish it. Once you do, it should run like a cut cat.
Also, a good reference on your needles is 1 1/2 turns out, from gently seated on your low speed and 3/4 turn out from gently seated on your high speed. Take it to the lake and fine tune the adjustments. I have found on those old 5.5's, the high speed likes to run at around a half turn out and the low speed, about 1 1/4 turns out. Make small adjustments and allow a few seconds of run time, to let the motor react to the adjustment.
Excellent motor you have. I own 4 of the of 5.5's

Yes it runs perfect on the high and middle runs perfect ,but down a low rpm (bad ) ck plugs look perfect ,hard to beleive there is hit /miss spark at low rpm ,I put new coils on it before I went out

 

[aaind]

Re: 1955 , 5.5 hp Johnson ,need little help

Yes did that ,and plulled plugs look great ,maybe its fuel flow ?? its going to or running on one cyl on very low rpm ,and just think its loading up ??