1973 johnson 115 wont start

Joined
Apr 21, 2014
Messages
24
Hi all once again, happy mother's day to all mums.
I attempted to start my new 115 johnson this week, but no success.
The wiring harness is hooked up correctly, all the wires, have continuity all along and across the big red connector, and a new ignition switch is properly hooked up, and new spark plugs.
The motor cranks but I have no spark on any of the coils.
I suspect the last owner might have shorted out the ignition box, but would like to make sure.
What is the correct procedure to troubleshoot the complete ignition system?
I am currently looking into the cdi electronics troubleshooting guide.
What is dva output as refered to in troubleshooting guides?
Thanks in advance my friends!
 
Last edited:

papapike

Cadet
Joined
Sep 9, 2006
Messages
17
Re: 1973 johnson 115 wont start

I have a 1973 85 hp that won't start either. I replaced the power pack and still no spark. Plugs are new. Someone said it may be the stater but I'm not sure what is involved with that yet
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 1973 johnson 115 wont start

You may be able to rent a DVA (peak-reading voltmeter) from a local auto parts store. The CDI guide is one of the best for these older units. You can also try a test. Disconnect the control box cable at the engine end. Jump the starter direct with a set of automotive jumper cables. If you get spark at the plugs, then the problem is in the wiring harness or control box, even the key switch. If you still have no spark, the problem is in the engine's ignition system.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1973 johnson 115 wont start

Disconnect the black/yellow wire from the pulse pack once and see what happens.
 
Joined
Apr 21, 2014
Messages
24
Re: 1973 johnson 115 wont start

Allright here goes.
I tested with the red connector plugged in, no spark.
Black/yellow wire disconnected at the power pack, no spark.
Voltage regulator unplugged, no spark.
Unpluged red connector, no spark.
Uuplugged black/yellow wire, no spark.
Unplugged regulator, still no spark.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1973 johnson 115 wont start

Go to the CDI Electronics site for test procedures.
 
Joined
Apr 21, 2014
Messages
24
Re: 1973 johnson 115 wont start

I don't know how to do the dva test, im not sure about the procedure, is that with the motor cranking or a static test?
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1973 johnson 115 wont start

Motor cranking. Static tests are done with an ohmmeter.
 

threedimensions

Recruit
Joined
Jun 22, 2014
Messages
2
So I've got a 73 50hp electric start outboard and it won't turn over. I've got spark, replaced the coils, she'll spin freely, but just won't start. Any thoughts?
 
Top