1965 Johnson 40hp point & plug gap

[fishon71]

Got an old Johnson 40 hp model# 40502 that's not running right - for starters could you please advise plug & point gap and maybe a quick overview of the carb adjustment (carb was soaked and cleaned) thanks

 

[kfa4303]

Re: 1965 Johnson 40hp point & plug gap

Champion J6C plugs gaped at .30-.35 and points gaped at .020" should be good. Here's a link on how to dial in your carb too (http://forums.iboats.com/showthread.php?t=167352). Just make sure you test your motor in a tank with water filed up to an inch or so below the exhaust. these old gems won't run on muffs.

 

[fishon71]

Re: 1965 Johnson 40hp point & plug gap

I put new coils in and pushed them as far back as they go towards the crank, is that the right thing to do? Now it will not start, I have spark on both cyl but it just about runs but only while the starter is turning it over.

 

[Tim Frank]

Re: 1965 Johnson 40hp point & plug gap

http://forums.iboats.com/showthread.php?t=294072

 

[kfa4303]

Re: 1965 Johnson 40hp point & plug gap

Hi fishon71. The coils can be a little tricky to to get set up just right, but you're on the right track with regards to pushing them close to the center/crankshaft. However, sometimes the magnet on the flywheel can strike them if they protrude which keeps the motor from turning over properly. See the thread posted by Tim Frank. Be sure all of the wires are tucked out of the way too so they don't become frayed.

 

[fishon71]

Re: 1965 Johnson 40hp point & plug gap

Okay got it to run again but flooded out and will not start after playing with the low idle mixture setting. Does it make sense if you screw in the low idle it reduces the air and gives it more gas or is it the other way around?

 

[Tim Frank]

Re: 1965 Johnson 40hp point & plug gap

Other way around.
Check the "Top Secret File" at the top of these threads; it contains a great description of how to do just about anything required to these carbs...

The current spark plug spec'd/rec'd for that motor is J4C, not J6C...gap at 0.030".

 

[kfa4303]

Re: 1965 Johnson 40hp point & plug gap

Okay got it to run again but flooded out and will not start after playing with the low idle mixture setting. Does it make sense if you screw in the low idle it reduces the air and gives it more gas or is it the other way around?

Other way around. When you twist the needle(s) in the motor will run leaner (less fuel to air) and the rpms will go up. They'll go down as you back the needle out and the mix becomes more rich. The trick is to find the balance. Adjust the needle is 1/8 turns and wait about 5-10 seconds after each adjustment to note the effect. You may need to loosen the brass nut/bushing that the needle passes through so you can turn the needle, but be sure you snug it back down. Here's a link that should help you get your carb set up.


http://forums.iboats.com/showthread.php?t=167352

 

[kfa4303]

Re: 1965 Johnson 40hp point & plug gap

....ooops! yup .030 gap.