6HP Johnson Tune Up

[NoExcuses]

Just picked up a 1985 Johnson 6HP, it replaces my 4 stroke 6HP, I'm really amazed with the difference in power of these two "6HP" engines but I'm having issues with idling and starting. I've been told to use premium gas versus the 87 octane I used the first time with it. Any other tips to make it start/idle better?

 

[oldboat1]

Likely not the gas. People choose higher octane to avoid ethanol mix -- attracts water, etc., etc. Make sure to use 50:1 oil mix with good marine two-cycle. You may need some carb adjustment, but should replace the impeller as a first priority.

 

[racerone]

There really is no such thing as a " tune up " any more.-----Electronic ignition .----Timing does not go out of adjustment.---Fixed jet carburetor.----So post compression test numbers.

 

[Crosbyman]

well carb looks old style with top idle drip chamber which may be gummed up . removal/inspection may be worth while since idling is poor

see old design...built into your " modern carb"

Seen recent comments on high octane which indicated it serves no big advantage

High octane has a bit higher flash point than 87 octane gas may be a disadvantage for your motor . Try 87 with common fuel saver like 2+4D etc...

Seafoam helped my snowblower cough.... some don't like it :-( some do