Johnson 115 hp No spark to 1 cylinder

[CaptainHook]

Just put a 1990ish Johnson 115hp on a boat for a buddy. The motor fires right up with no problems but wouldn't idle so I started checking things out.

Found one cylinder not firing. Changed the coil and still no fire. Use a jumper wire to another cylinder's connections and the coil fires.

This motor only has one powerpack. Could this be bad? Or does the signal to fire come from another component?

 

[emdsapmgr]

Re: Johnson 115 hp No spark to 1 cylinder

Not suprised that you found the coils ok. They're pretty reliable. Yes, it is possible that the pack is bad. They are a common failure item over time. The other components are the stator and timer base. All of them can contribute to a "no spark" problem and they are all pretty expensive. It will pay you to do some electrical troubleshooting on each component as described in the factory service manual. You can get an original factory manual from Ken Cook Co., in Milwaukee.

 

[bktheking]

Re: Johnson 115 hp No spark to 1 cylinder

Could be a number of things

http://www.cdielectronics.com/downl...1978-1998 65-140 HP (Without Quick-Start).pdf

Stator, powerpack, timer base??? test test test.....cheaper that way!

 

[bktheking]

Re: Johnson 115 hp No spark to 1 cylinder

Congrats , 3000 posts EMDSAPMGR!

 

[CaptainHook]

Re: Johnson 115 hp No spark to 1 cylinder

I do not have a manual for this and was trying to get it going asap. I have another powerpack, timer base, and stator. But they are from a non-running parts motor.

I don't want to just swap everything out without knowing what is going on. Anyone know how to test these components with a meter?

 

[steve6]

Re: Johnson 115 hp No spark to 1 cylinder

just swap the power pack , it shouldn't be too hard to do just the pack.

i just had one go back on a older johnson =\

 

[CaptainHook]

Re: Johnson 115 hp No spark to 1 cylinder

I will swap the power pack. But would still like to know how to test these components.

 

[steve6]

Re: Johnson 115 hp No spark to 1 cylinder

i couldn't get an answer either on my post. i come from the snowmobile world and relate them to what we call CDI units, which are not testable most of the time either.

 

[emdsapmgr]

Re: Johnson 115 hp No spark to 1 cylinder

The factory service manual typically shows two types of testing for these ignition components. Testing is done with the components still on the engine, but with connectors unplugged. There is usually a type of voltage test which requires a special peak-reading voltmeter. There also is usually an ohms test. You can get a factory manual from Ken Cook Co., in Milwaukee. These tests are done so that an owner does not have to purchase all of the components and just swap them out untill you find the defective component. You are in a unique situation if you have duplicate ignition components on hand. It's as easy to just swap parts as it is to diagnose them per the manual. Start with the power pack. It's easy to swap and typically fails more frequently than the stator or timer base.

 

[bktheking]

Re: Johnson 115 hp No spark to 1 cylinder

Could be a number of things

http://www.cdielectronics.com/downl...1978-1998 65-140 HP (Without Quick-Start).pdf

Stator, powerpack, timer base??? test test test.....cheaper that way!

Look at the PDF I posted, it's a good starting point.

 

[CaptainHook]

Re: Johnson 115 hp No spark to 1 cylinder

Thanks for the help. I am going to get started!!!!