1983 Johnson 50 problems

[NICKSCHMID]

Sorry this is a long post. I have 1983 Johnson 50 BELCTA I took in on a trade and found out the power head was replaced with a 1985 power head. When I first started it up it had a misfire and was running rich. So I put new plugs in and rebuilt the carbs. So I started it up and it was still misfiring and but now it seemed like it was running lean. So I messed with carb some more and start it back up and the engine ran away on me. So I found out I had an air leak at bottom crank seal. So I take the whole engine apart and resealed it. So I get it back together and ran it no misfire and the idle was real low rpms so I tried adjusting it and nothing would happen. So I gave up on for a week and I came back to it and start it up and it started misfiring again. So I put spark plug wires started it up and still misfiring. So I got a spark tester and a peak voltage adapter and set the spark tester to 7/16 gap it was a weak spark on both cylinders. So I check the stator and the voltage was good. So I check voltage to the coils from the power pack and both were real low. So I thought it was a power pack thinking there is no way for both coils to be bad. So I replaced the power pack and started it up and it still had a misfire. I checked the power from the power pack to the coils and it still reads low voltage. Seems like anything I do to this engine it doesn’t do anything to it. Should I try new coils? I’m at a loss right now and getting tired throwing money in to it. Has anyone else had any problems like this. Any input would be great thanks in advance.

 

[juno pierrat]

with dva, check charge coil under flywheel

 

[juno pierrat]

well after looking around . the 83 and 85 ignition parts under flywheel are totally different, is yours a basic one piece donut shape, if so I think it still an 83

 

[flyingscott]

The 83 ignition will work just fine on an 85 block. You need to know which stator assembly you have for testing. Very possible they bought the 85 as a shortblock and used your 83 parts. You may want to check the carb jetting also and did you check compression.

 

[juno pierrat]

yep, the blocks thru the 80's have few changes, but bolt on stuff did change, " up grades", 83 to 84, ignition and carbs, 88 to 89, ignition, carbs and head. i'm currently have an 89 head on a 87' 48spl, i can actually check the thermostat with just one wrench.
don't mean to get off subject/hijack yes compression number would be good info

 

[NICKSCHMID]

The compression on both cylinders are 110
checked the ignition parts under the fly wheel with the dva tester and the voltage was good. Here a couple pictures of the ignition parts under the flywheel.

 

[juno pierrat]

that's an 85 ignition, is that black goo under the black charge coil? if so its bad. the white coil is the sensor coil and the two a like is the stator.

 

[NICKSCHMID]

Yeah the charge coil does have black goo under it. I’m new to these engines so I didn’t think much of it. I’ll pull the fly wheel back off and replace it. Thanks

 

[Klink]

Are you checking the charge cowl output (and everything you've worked on) according to the factory original service manual specs?

 

[NICKSCHMID]

Yeah I think, this site here is what I used

 

[NICKSCHMID]

I also used this one

 

[Klink]

Yeah I think, this site here is what I used

When I did my friend's Evinrude 1990 3 cyl 70hp, I found the CDI instructions too general, I used the original Evinrude manual instead.