Stop Switch Sticking?

[BaitThrower]

Hey all...

Johnson 86 model 15hp.

Sometimes I can't get her to restart after shutting down. Happens only every now and then... I let it sit for a while longer and then she starts up again... I know its not fuel related and am suspecting the stop switch is sticking or staying grounded. It is one mounted on the end of the tiller arm/throttle and you kinda have to give it a good push in to stop, and it doesnt seem to spring back (but not if and how much it should).

If this happens again when out on the water, should I just unscrew the ground wire from the its grounding point on the block and then try and start it? If it starts with ground wire disconnected from block, then that would confirm the stop switch is probably sticking grounded and not allowing the electrics to power up yes?

Could I also test it at home with a multimeter? i.e. put multimeter on ground wire... start up engine, watch reading, then press stop switch and see what reading is? What setting on the multimeter would I use and which probe? If it is sticking, would it give me a constant reading after being stopped rather than a single pulse reading? (not really sure if this is how it would work with a multimeter on the ground wire?). Help!

Thanks in advance!

 

[tashasdaddy]

Re: Stop Switch Sticking?

i don't know if i would use a multimeter, because the kill switch, grounds the coils. depending on what the motor is putting could blow the meter. you are probably right, you could just leave the existing switch and route around it with a lanyard switch, just drill a hole in the lower cover where it would fit, would also be much safer for you.
necessity, the mother of invention, even if it is under a shade tree.

 

[BaitThrower]

Re: Stop Switch Sticking?

i don't know if i would use a multimeter, because the kill switch, grounds the coils. depending on what the motor is putting could blow the meter. you are probably right, you could just leave the existing switch and route around it with a lanyard switch, just drill a hole in the lower cover where it would fit, would also be much safer for you.
necessity, the mother of invention, even if it is under a shade tree.

Ok thanks, but next time I can't start it, I should just discconect the ground wire coming from the stop switch to its location on the engine block and if it starts up straight away I would confirm the stop switch sticking is the problem yes?

 

[tashasdaddy]

Re: Stop Switch Sticking?

i do believe so.

 

[F_R]

Re: Stop Switch Sticking?

Not being 100% familiar with the accessability of the wires, it would be better to disconnect the stop switch from the power pack if possible.

There is high voltage in that wire coming from the power pack to the switch. The switch just grounds out that high voltage, which kills the ignition. What I'm getting at is that you might blow your multimeter from overvoltage if you make the wrong tests. You can also shock the snot out of yourself if you get hooked up with it.

 

[BaitThrower]

Re: Stop Switch Sticking?

Not being 100% familiar with the accessability of the wires, it would be better to disconnect the stop switch from the power pack if possible.

There is high voltage in that wire coming from the power pack to the switch. The switch just grounds out that high voltage, which kills the ignition. What I'm getting at is that you might blow your multimeter from overvoltage if you make the wrong tests. You can also shock the snot out of yourself if you get hooked up with it.

Not really possible to disconnect from the power pack. The switch has one wire going to power pack, and another directly to a ground point on the engine block. If I remove the engine block ground wire, I would only do it when engine not running, so should be no risk of electric shock etc.

 

[Xcusme]

Re: Stop Switch Sticking?

You can use a multimeter to test the switch. Disconnect the plug going to the power pack. Place the meter in low ohms. Place the Red meter lead to power head ground. Place Black meter lead to wire in plug, going to switch. Press Stop button, meter should fully deflect, showing continunity. Release Stop button, play (strum) wire going to plug jack, all along it's length, watching for any meter needle deflection. There should be no movement of the meter. If any part of that wire goes to ground, meter will deflect, indicating a short to ground, and thats not good. While pressing and releasing the Stop button, you should see the switch action. If you decide to run the motor with the switch disconnected, you'll have to choke the motor to stop it from running.