Johnson 35 loses spark on one cylinder

Greybeard

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May 26, 2003
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7
I have a 1980 Johnson 35 HPEL (#ES085086). I bought it 3 years ago and immediately had it completely overhauled. It ran perfectly until about the end of last season when it started to occasionally lose power and bog down with what I thought was a gas/fuel supply problem. I completely emptied the tank and fuel lines and replaced it with fresh gas/oil mix and that did not change anything. I checked the fuel filter and it is perfectly clean.<br /><br />The problem has become much worse lately - to the point that the motor only fires on both cylinders after it is started cold. Once I restart the motor after it warms up it only has spark on the upper cylinder. If I hold the throttle wide open after the motor bogs down it occasionally tries to fire on the second cyclinder (this happens once about every 5 minutes). I have replaced the spark plugs - they were oil fouled - but that has had no impact on the problem.<br /><br />I'm certainly not an outboard expert, so I am looking for suggestions on where I should look next. Is this a stator problem, perhaps?
 

JB

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Mar 25, 2001
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45,907
Re: Johnson 35 loses spark on one cylinder

Ahoy, Greybeard.<br /><br />It could be stator, powerpack, coil, plug wire or plug.<br /><br />You can eliminate the plug, wire, and coil by swapping them.<br /><br />It sounds like a heat related problem, which is usually the powerpack. You can verify it by spraying a freeze spray (available at radio Shack) on the powerpack to see if it comes back on.<br /><br />Good luck. :)
 

shannoninark

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Mar 14, 2003
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Re: Johnson 35 loses spark on one cylinder

I have a Johnson 175 that was dropping cylinders and i found that it was a powerpack and voltage regulator. i dont know if your motor has a reg. but i would assume that it is the powerpack. If it does have a voltage reg. i would start there, my reg. caused my pack to go out. With both replaced it runs like a top.
 

Greybeard

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May 26, 2003
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Re: Johnson 35 loses spark on one cylinder

Thanks for the replies, JB and shannoninark. I have already changed plugs and swapped the new ones between cylinders to no effect. Therefore, my next move will be to swap the plug wires and coils and keep working back from there. Wish me luck. ;) <br /><br />Again, thanks. I'm new to the board and really appreciate how it is run.
 

Walker

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Jun 15, 2002
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Re: Johnson 35 loses spark on one cylinder

Another thing to check is the ground straps on the coils. Clean them and the block where the make contact.
 

Greybeard

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May 26, 2003
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7
Re: Johnson 35 loses spark on one cylinder

I used a spark tester to verify that I am getting spark on the upper, but not lower, cylinder. Cleaning the contact areas on the wiring and the block did not make any difference. I also swapped the plugs - and the no fire status of the bottom cylinder did not change.<br /><br />Next, I would like to swap the coils/plug wires, but I am unsure how to proceed. Please bear with me while I ask a few possibly stupid questions.<br /><br />1) How do I swap the coils? They are wired directly into the 3 prong plug, and swapping or replacing them appears to be a wire cut and splice job - or can the wires be removed from the plug? Please advise - I haven't worked on outboards before and this doesn't look like anything that I am familiar with on automotive engines.<br /><br />2) Also, I have found replacement parts including coils and plug wires on sale online for my engine, but I am a bit confused about the plug wire/coil junction. The coils and plug wires on my motor appear to joined together as a single unit. Or, is there a way to remove the wires from the coils? <br /><br />3) Additionally, I find both a One Post Coil and a Two Post Coil listed for motor. How do I know which I need? (I took a picture of my coils with my digital camera, but can't figure out how to submit it.)<br /><br />4) Finally, I picked up a SELOC repair manual and am having difficulty locating a ohmmeter like they describe in their diagnostics test that has Low Ohms (Rx1) and High Ohms (Rx1000) settings. I haven't found a plain ohmmeter, and these settings do not seem to match what is available on the multitesters that I have found. Where might I find a simple ohmmeter with low ohms/high ohms?
 

Greybeard

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May 26, 2003
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7
Re: Johnson 35 loses spark on one cylinder

A friend who is an engineer is lending me his Fluke tester, so I am back on track for doing diagnostics. I'd appreciate any help you can give me on my other questions. :)
 

Greybeard

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May 26, 2003
Messages
7
Re: Johnson 35 loses spark on one cylinder

I used a multitester to perform the first 8 ignition tests in my SELOC repair manual:<br />1) Key switch/kill button<br />2) Three prong connector I get spark on the upper, but not lower, plug - as has been my problem.)<br />3) Ignition coil test, primary winding<br />4) Ignition coil test, secondary winding<br />5) Sensor coil resistance<br />6) Sensor coil, testing for a short<br />7) Charge coil, output test<br />8) Charge coil, testing for a short<br /><br />All the other tests check out fine. I do get a difference in readings on the upper and lower plug wire in test 4, although both are within the 275 +/- 50 ohm range. I get 276 ohms on the upper and 304-310 ohms on the lower.<br /><br />Can anyone offer me advice on how to proceed from here?
 

Greybeard

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Joined
May 26, 2003
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Re: Johnson 35 loses spark on one cylinder

I've been waiting a week without any answers - so I'm giving it another try.<br /><br />I get spark on only one cylinder. The coils test out fine with an ohmmeter, but I want to be sure the coils aren't bad before I go to the expense of replacing the power pack and voltage regulator.<br /><br />I'd like to swap the coils, but I'm not sure how I should do it. They are wired directly into the 3 prong plug, and swapping or replacing them appears to be a wire cut and splice job - or can the wires be removed from the plug? Please advise - I haven't worked on outboards before and this doesn't look like anything that I am familiar with on automotive engines.
 
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