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65 Johnson 18hp won't stay running

It originally called for 50:1 in 1965.-----Not sure where your 32:1 comes from.------Some simple trouble shooting will find the issue.
 
Got all my fuel lines replaced. Took apart carb and cleaned it out (was already pretty clean). Got motor running ok but it still doesn't want to idle. I can push the throttle linkage with my finger and it stays running. So, 2 questions. First, where should I set low speed jet as a starting point? I tried 1.5 turns out and kept backing it out 1/4 turn at a time about 8 times so had it 3.5 turns out when I decided it wasn't making a difference. Second question, the little rubber wheel that is connected to the linkage, looks slightly grooved. What is that wheel called and can I bend the linkage a tiny bit to get a bit more rpm at idle? I noticed when I had the carb off that with the motor in forward gear and throttle twisted all the way, the butterfly in the carb is only opening about half way. The groove on the wheel doesn't look nearly deep enough to account for the other half of the butterfly travel.
 
Check part #34 on the slow speed needle.----Find it and check it.----If thread is tight you might have issues.----Perhaps the slow speed needle is not adjusting.
 
It is a little tighter than it was because I tightened the packing nut a hair too much but I can still easily turn the jet with my fingers. I can feel it seat so it's definitely threading in there
 
Cable said:
Trying to upload photo

Ok. Doesn't seem to be working but everything under there basically looks new. No corrosion at all. Can the coil and condenser be checked with a multimeter?
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Yes, there are several Youtube videos that are very helpful.
 
Cable said:
The coils can start to fail once they warm up a little? It runs like it's new when it's cold. I can give it more gas and it revs up like it should. Good throttle response. Once the rpms begin to drop, I can give it more gas and it will keep running but after about 5 minutes it dies even with the throttle all the way open.

Is there a way to test the coils with a multimeter?
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Yes, that is the typical reason for failure and yes you can test them with a multimeter. See Youtube videos.
 
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