'98 50HP Johnson won't idle

standfas

Cadet
Joined
Aug 17, 2003
Messages
24
My 50HP Johnson will idle while on the muffs but won't when in the water. How do I advance the idle speed?<br /><br />Thanks,<br />Keith
 
D

DJ

Guest
Re: '98 50HP Johnson won't idle

Advancing the idle speed is masking the symptom, not repairing the problem.<br /><br />Most likely, you are running on one cylinder-only.<br /><br />1. Check spark, on both. Should jump 1/2" with strong blue spark.<br /><br />2. Check compression on both. Should be over 100 and very close to each other.<br /><br />If both of those are OK, you probably have a fouled carburetor, for that cylinder.
 

standfas

Cadet
Joined
Aug 17, 2003
Messages
24
Re: '98 50HP Johnson won't idle

Hello,<br /><br />I had the boat in the water last night. The motor idles nicely while in neutral, but won't idle while in gear. When I put it in gear, I have to give it a little throttle to keep it from stalling. The motor runs great once I get above idle speed. Comes up on plane with no trouble. Runs strong while on plane. According to GPS I hit 33mph with no stumbles or sputters at all.
 
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