Intermittent Ignition Problem 1982 70hp Johnson

[South Paw]

Hello and happy new year all.

I went for a fish yesterday and moved around a few times when the last move back to the ramp was called i had no ignition. Nothing completely dead.
The battery was/is fully charged, all accessorise functioned, Tilt/Trim worked. The key switch was dead. No clicking of the choke solenoid. I would repeatedly press the choke in on the ignition switch and would get it to work every now and then but couldn't get it to fire.
Had to get towed back in. Water was quite lumpy and when almost at the ramp i tried again and the outboard fired right up.
I replaced the ignition switch about a year ago so i suspect a loose connection or faulty switch.

The engine is a 1982 70hp Johnson with the original controls.
One question i have is if the neutral safety switch is faulty/engaged and prevents the outboard from firing does anyone know if the choke will still function?
I guess i could check providing that on the trip home it still fires. If everything checks out in the controls ie the switch wiring looks good is there anywhere on the outboard itself to check eg a loose earth or bad wire that would cause the same symptoms?
I kinda wish it had not restarted as it makes this type of problem harder to diagnose.
Thanks for reading and all replies appreciated.

 

[jbjennings]

Re: Intermittent Ignition Problem 1982 70hp Johnson

I would make a special effort to go through the entire ignition system if it's been a while since you've done it and clean every single connection, particularly battery grounds. Of course the parts in your controls as well. Sometimes a wire will get loose if it's not properly crimped in the connector. I'd say a bad ground is the most likely problem.
JMO,
JBJ

 

[Bosunsmate]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Yes the choke will still function.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Thanks for the replies.

@Bosunsmate, Thanks. Sounds like it's at the key switch then. Will open up the controls in the morning. Can i loctite the terminal screws on the switch or will it mess up conductivity?

 

[Fleetwin]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Clean and tight is all you need. They shoiuld not come loose. They didn't in 30+ years from original.

The nuetral safety switch will also stop it from "turning over".

 

[oldman570]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Lock Tight on the screws would not be my first choice, as it can make it very hard to get the screws loose without bending or braking the brass terminals off the parts. I would get a tube of dialectic grease at the local auto supply store and use it on any and all electrical connections. It is made to keep the connection from going bad when used in a moist/water environment. Liquid rubber tape will also do the job and can be bought at most electrical supply outlets. JMO
Oldman570

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Thanks guys. No loctite then.
oldman570, iirc the original key switch contact screws had a good dose of liquid tape on them. I'll know in the next hour as i'm about to go out to open it up and see after my coffee.
Thanks all.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Clean and tight is all you need. They shoiuld not come loose. They didn't in 30+ years from original.

The nuetral safety switch will also stop it from "turning over".

I do have a new neutral switch, maybe i'll just swap it out incase it's faulty.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Well everything is clean and tight with nothing obvious under the cowling or in the controls. I'm gonna swap out the neutral switch now while it's apart just to be safe. There's maybe a 1/5 of a tea spoon of grease on the shift lever and old switch.
I sprayed contact cleaner in the big red cannon plug.

Correct me if i'm wrong, if the cannon plug was not quite tight would i be right in assuming the trim would still work and so would my accessorise?

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Yes the choke will still function.

Yep, i just fitted the new neutral switch and i can verify this. I'm not convinced at all that was the problem because i lost choke also, actually i highly doubt it now, but it's done.
Maybe just a dickey ignition switch and i gave the original one to a friend since his crapped out...that'll learn ya dearn ya...shoulda kept it.

Anyways everything works as it should for now. I'll just have to go through everything else again. grrrrrrr

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

I'm gonna make myself a remote starter switch incase i need it.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

A video of my home made remote starter in action.

 

[Bosunsmate]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Thats a Good set up.
Hope your tilt still works if you have to clip that on in Bass STrait.
I wouldnt leave that on unless you are sure you arent going to have a clip come off and short to ground

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Thats a Good set up.
Hope your tilt still works if you have to clip that on in Bass STrait.
I wouldnt leave that on unless you are sure you arent going to have a clip come off and short to ground

Haha cheers, yeah tilt/trim works and so does the ignition. If it plays up again as per my original post then at least i have a way of starting the ol' Johnno. I've gone through everything i can. If it happens again i have a new ignition switch on the way in case that's faulty and i'll have to start checking the main cable if it continues.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

Guys, can anybody tell me if there have been any issues with Johnson/omc replacement ignition switches?

 

[emdsapmgr]

Re: Intermittent Ignition Problem 1982 70hp Johnson

The replacement key switches from Bombardier are ok. Just be sure that you get it installed with the drain hole facing downward. If they get rainwater in them, they act up... Also, pull out the engine's ignition fuse from it's holder-by the solenoid on the port side of the engine. Sometimes the contacts that hold the small fuse will get corroded and won't transfer voltage properly. I'd try to jump the starter direct with a set of automotive jumper cables to a known strong battery. If it turns the engine over, the starter is ok. Then check out the starter solenoid. If the internal solenoid contacts get burned (with age) it won't transfer current to turn the starter.

 

[South Paw]

Re: Intermittent Ignition Problem 1982 70hp Johnson

The replacement key switches from Bombardier are ok. Just be sure that you get it installed with the drain hole facing downward. If they get rainwater in them, they act up... Also, pull out the engine's ignition fuse from it's holder-by the solenoid on the port side of the engine. Sometimes the contacts that hold the small fuse will get corroded and won't transfer voltage properly. I'd try to jump the starter direct with a set of automotive jumper cables to a known strong battery. If it turns the engine over, the starter is ok. Then check out the starter solenoid. If the internal solenoid contacts get burned (with age) it won't transfer current to turn the starter.

Thanks for the reply. The starer is fine i believe the switch is dicky. It played up again today, just the once, when it does it fail to power the enricher/choke solenoid also, that's what leads me to think the ignition/key switch is dicky.
Is there a better switch brand out there i should order ?