1978 140HP Johnson Turning Key Does Nothing

[Patto248]

Hello.
I have a 1978 140hp Johnson outboard and most of the times it will start fine, however sometimes when I turn the key it will not do anything, not click, nothing but all the other electronics are working, and it may do this for a while, then all of a sudden it will work again. When it doesn't work you can jump the solenoid and it will start. I have also test the ignition switch with a test light and that seems to be fine and the solenoid does to, so what else could it be l, I've bypassed the neutral safety switch to so it can't be that. Having trouble now.
Thanks
Jake

 

[F_R]

The trouble could be anywhere in the circuit. You need to do some voltage checks while it is not working. But begin by checking both battery cable connections at both ends. Don't just look at them, take them apart and and clean them shiny bright.

 

[jimmbo]

Welcome to iboats

Since it is intermittent, it might very well be the ignition switch. It could also be a broken wire in the harness. When it acts up, hold the Key in the start position and turn the motor from port to starboard and back, try varying the trim angle. Or wiggle the harness where it engine cowl. Inside the control box, check for and place where the linkages inside may contact the wires as they are moved.

40 yrs ago I took my dads boat across the lake, after a few hours I turned the key to start the engine. It cranked but didn't start, when I let go of the key the engine continued cranking. I got the cowl off, found an adjustable wrench and unhooked the battery cable from the solenoid, but by then there was smoke coming out of the starter. I was really glad I put the kicker motor on the boat that day as it would have been a miserable 11 mile walk along the shore(undeveloped). Still took over 2 hours to get home, The problem was the Ignition Switch, but the starter was pooched because of it. Looking back we may have been able to hot wire it, then rope start the engine, it was only a 90hp

 

[interalian]

Check/wiggle the shift handle in neutral - there's a safety switch in there. I've had mine fail to crank and wiggling the shifter got it working.

 

[racerone]

But, but, the poster says he has bypassed that nuetral safety switch !

 

[Patto248]

I'm pretty sure the ignition switch Is fine because I tested it with a test light at the back of it and the light come on when I turned the key. Ive tested most of it with a test light and it seems fine when it's still not working. Will a multimeter show me different results?

 

[racerone]

Electrical trouble shooting amd opinions are all over the place.--------I would pull the stater apart for inspection.----And inspect the wee ground wire on the solenoid..---No money needs to be spent doing those and it is easy !

 

[F_R]

If you get into tests (after the cables), I begin at the solenoid. Check the voltage at the red/yellow wire as you turn the key to start. Should show battery voltage. If it does not, the problem is ahead of that point. But if you have the volts and it doesn't crank, the problem is between there and (including) the starter. Make additional checks accordingly

 

[wrench 3]

When it won't crank, connect your test light across the two small terminals on the solenoid (ground clip on one and probe on the other) and turn the key to start. If the tester lights up but the solenoid doesn't click, then you have a bad solenoid. If if doesn't light, then you need to find out if you've lost the power to the yellow/red wire or the ground to the black wire. Both can be tested with a light but the circuit must be under load for the test to be valid. (key turned to start) Also the fault must be there before and after the test for it to be valid.

Sorry F_R your post wasn't there when I started typing.

 

[oldboat1]

What do you mean in your first post when you "jump the solenoid" to get it to start? (could mean a few different things.)

 

[Patto248]

Thanks for all the responses. I mean that when I put a jump starter on the top post of the solenoid it will start the motor. I have tested the solenoid with a test light and when I turn the key it does in fact light up.

 

[F_R]

As you indicated at the onset, the problem is intermittent. So all the tests are meaningless unless you happen to catch it while it is in the won't start mode. by the symptoms, I'm betting on cable connections or starter motor. Any takers?

 

[Patto248]

Sorry I should have said, I have done all these tests when it wasn't working

 

[wrench 3]

Don't forget that you need ground to the solenoid as well to make it work.

 

[oldboat1]

think I'll guess a connection issue. It sounds like battery power sometimes isn't getting to the large solenoid post (incoming side -- which I think would be the top post that you jumped). But guessing.

 

[jimmbo]

Is the ground wire off the Solenoid securely grounded?

 

[jakedaawg]

Put a solenoid on it and be done with it. You already tested it and found it bad. Had power but no go. Jumped big posts and it went. All that equals bad solenoid.

 

[Patto248]

I'll have another look and clean up all the wires. Yes I have just redone the solenoid ground cable, the old one was looking pretty weathered so hopefully it was that. If not I will look into a new solenoid, do yous have suggestions for which one to get?? Thanks

 

[jakedaawg]

I'll have another look and clean up all the wires. Yes I have just redone the solenoid ground cable, the old one was looking pretty weathered so hopefully it was that. If not I will look into a new solenoid, do yous have suggestions for which one to get?? Thanks

OEM #0383632

 

[jimmbo]

Iboats has one listed as 0586180