5.5 seahorse starts but then??

[OhioLowell]

Hello all. I've looked thru the search files and didn't come across this question any where. I have a 5.5 Johnson seahorse motor. I've pulled the carb off and cleaned it and reinstalled it, removed the gas tank and rinsed it and reinstalled it, repalced the plugs and gassed it up with new 50:1 fuel. Prime the carbs and low and behold it fired on the second pull. It ran rough at the start position,but it was running. When I tried to make the motor accelerate by moving the throttle lever the motor dies. I have tried to adjust the carb fuel screws and have cleaned up the idle a good amount, not perfect but much improved. However the motor still dies when the throttle is moved.<br /><br />I don't knwo why this is but it'll always do it, if there is any info or help anyone can lend would be greatly appreciated. Thanks in advance.<br /><br />Lowell

 

[MCM]

Re: 5.5 seahorse starts but then??

Lowell, have you got a year or model# for that motor, I'm not sure 50:1 is the mix you want to be using for starters

 

[MCM]

Re: 5.5 seahorse starts but then??

Lowell, one of the reasons I asked about the yr. & model# is that if it is a 5.5 Johnson, they were made between 1954 & 1964, in which case you should be using 24:1 mix.

 

[emckelvy]

Re: 5.5 seahorse starts but then??

Definitely gots to run rich oil, that motor, depending on the year, has babbitt bearings in most or all of the crank surfaces and needs more oil than a 'fully jeweled' (i.e. roller/needle/ball bearing'd) motor.<br /><br />Regarding your running problem, sounds like maybe the main jet is set too lean. Lightly seat it clockwise then back out 5/8-3/4 turns and see if that makes a difference. <br /><br />One thought, does it make any difference if you apply a little choke while attempting to rev up? Trying that may tell you something about the carburetion.<br /><br />You don't say if you've been under the flywheel or not, but ign problems can make it run poorly. If the coils are cracked or 'oozing' material, they are shot. If the points are dirty or gapped incorrectly it may not rev up. I worked on an old 18HP Johnson recently that didn't like the points gaps too wide or it would drop a cylinder as soon as you opened the throttle.<br /><br />If you need new ign parts check out this website, they have decent prices on OMC ign parts:<br /><br />www.boatfix.com<br /><br />HTH........ed

 

[OhioLowell]

Re: 5.5 seahorse starts but then??

What is the main jet screw? Where is it located? I'll check the serial number and model number tommorow. Do I have to remove the fly wheel to get to the points and stuff. <br /><br />Thanks,<br />Lowell

 

[MCM]

Re: 5.5 seahorse starts but then??

Lowell, <br /><br />The main jet is on the carburetor, and yes the points would be under the flywheel. Its best to know exactly what motor you're dealing with though before making any adjustments

 

[JasonJ]

Re: 5.5 seahorse starts but then??

Ohio, if it has the High Speed adjustment and the Low Speed adjustment on the carb, you need to get it in the water, and run it wide open, under load, in gear and adjust your High Speed screw until the motor runs perfect. THEN you bring it down to idle, in neutral, and adjust your Low Speed until the motor idles perfect. <br /><br />Sometimes the coils are bad or breaking down, and that can make it difficult to get these motors running good, but if you have good coils, points set to .20, and the high and low speed adjustments set right, these motors run like sewing machines...

 

[Paul Moir]

Re: 5.5 seahorse starts but then??

When the ignition system is healthy and reasonably timed, you will be able to draw about a 3/8" long spark off each spark plug lead to ground. If you want to see a complete teardown & fixup of the 5.5s ignition and carburetor, have a look here:<br /> http://www.outboard-boat-motor-repair.com/ <br />(Click 5.5, then procedure)<br /><br />I personally would rather see you use a harmonic balancer puller (cheap auto tool) and 3 1/4"-20tpi bolts to remove the flywheel than the "hit-it-till-it-comes-off" method:<br />

<br />Retorquing the flywheel nut is more critical than the article lets on. I would not want to go to sea with an engine with an incorrectly torqued flywheel nut as sudden and practically unrepairable loss of spark is possible.