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1976 johnson 55hp idle adjustment help

lukepeden

New member
i recently changed starter motors on my outboard and have been having trouble starting it properly. i adjusted the idle adjustments and can get it to gradually start while doing that, but once the engine goes cold i cant restart it. i have changed the adjustments 3 times and every time i do i will get it to start but it just wont start again. i am really new to boating and i would appreciate some help from someone who knows what theyre talking about.

so thanks in advance to anyone that can help.
 
(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note 1: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Note 2: If the engine should be a three (3) cylinder engine with three (3) carburetors, start the adjustment sequence with the center carburetor.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

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Proper Starting Procedure:

Pump fuel primer bulb up hard - Apply a slight bit of throttle to take the engine off idle - Turn the key to the START position and engage and hold the choke at the same time - When the engine starts (should start within six revolutions), release the key and the choke to its normal RUN position.

NOTE: Early model ignition switches DO NOT have the "Push To Choke" key feature but will rather incorporate a separate choke switch..... Later model ignition switches have the "Push To Choke" key feature.
 
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Good morning, I hate it when they don't post back too.
i came across this thread recently and was impressed by the willingness to share knowledge based on experience.
I bought a 1975 Johnson 50 HP long shaft last year. it was rebuilt just before i got it. It operated perfectly all last season. oh by the way, it has carbs from a 55 HP motor. this year it would not idle so a friend with lots of experience on old 2 stroke motors helped me get it running. problem is it cuts off when put in gear but only when in the water. currently the timing at idle is -8 degrees and still wants to cut off when put in gear. I wonder about the carburetor mismatch. Is it common to increase the carb size when cylinders are bored out? I also wonder if the motor will ever tune to the book spec. (-3 deg at throttle pickup). i have not yet tried the process that Joe Reeves describes above but plan to this weekend.

I hope this makes it to you and I promise to respond... because I really want to know.

old 50
 
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