Johnson 1999 50 hp will not turn off

[jrtax]

i have a 1999 Johnson 50hp and the key will no longer turn the engine off. Everything has been working fine but now I have to push the choke in to flood the engine. What all can I test to see what the problem is or does anyone have any ideas of what could be the problem. Thanks for any help

 

[Joe Reeves]

(Ignition Kill Circuit)
(J. Reeves)

A Black wire (ground) should lead from the powerhead to the powerpack. There will also be a Black/Yellow wire leading from the powerpack to a raised "M" terminal of the ignition switch. To complete the circuit, there will be a Black wire from the other "M" terminal of the ignition switch to ground.

When the key is in the OFF position = The two "M" terminals are connected,. effectively shorting/killing the ignition.

When the key in ON position = The two "M" terminals are not connected and the ignition is engaged.

 

[jrtax]

thanks, so what do I need to look for and how do I test to find the problem.

 

[Bosunsmate]

ground the black wire with yellow stripe from powerpack to the engine, does that turn it off

 

[jrtax]

sorry but what exactly do I need to do to ground the wire. just want to make sure I di exactly what I need to do

 

[Bosunsmate]

a black wire with a yellow stripe comes out of the powerpack. Follow that wire until you get to where it connects to its next wire, disconnect it there. Then touch that end of the wire (the end that is joined to the powerpack) to a bare part of metal on the engine.

 

[Bosunsmate]

if the powerhead is painted then add a bit of wire to the end and reach it around to touch the starter shell as thats often a bare metal shell. You can also sand off some paint on a bolt

 

[jrtax]

thanks a lot for the help I will try that this afternoon and let you now how it turns out.

 

[Bosunsmate]

If it doesnt work, take a photo of what you did so people can check you did it right

 

[jrtax]

ok I tried that last night and the wires including the yellow/black wire coming from the power pack go to a 5 wire plug. Looking at the yellow/black wire I noticed that the wire coming out of the other side of the plug ( not the part of the plug that is on the power pack side) only had a couple strands holding it to the plug. Once I pulled the plug apart those 2 little strands pulled completely out. Thinking that was the problem I took a piece of scrap wire and put it in the female part of the plug for the yellow/black wire and put the plug back together to connect the rest of the wires to bypass the bad connection. When I touched the end of the scrap wire to a bolt on the power head it killed the engine regardless of if the key switch was on or off. Next I connected the scrap wire to the yellow/black wire that had pulled out of the plug but the engine would no longer not cut off. What could be the problem. I tried to explain that the best possible. If something isn't clear I can re explain. Thanks a lot for the help.

 

[Bosunsmate]

Well sounds like the powerpack is ok.
Heres a diagam of the wiring
http://continuouswave.com/whaler/reference/ignitionSwitch.html
Sounds like you have a fault on that blackyellow wire from there back to the control box.
You need to check that the ground on the control is in place.
Have you a long length of wire?
If so touch one end to the control box and the other end to the bit of wire that killed the motor in your test.
If that kills the motor then its a problem in your switch or that black yellow wire from the control box to the powerpack

 

[Bosunsmate]

Thats assuming your control box is metal (most a)

 

[jrtax]

By saying I need to check that the ground on the control is in place, are you talking about making sure the ground is on the M terminal or is there a ground on the control box

 

[Bosunsmate]

check that the ground wire to the control box is in place/not broken.
then M afterwards

 

[jrtax]

will do.. thanks

 

[northface]

You can look near the ignition to see if there is a diode. Looks like a a big resin ball. If there is one, try turning off the switch when the engine is running and then disconnect the diode. Another test would be to use a meter to check for continuity. You should get current flow in only one direction. If it's in both the diode is bad.

 

[jrtax]

i think I might have figured it out. I took the control box apart and the yellow/black wire coming from the M terminal on the switch to the kill switch was cut and taped up bypassing the kill switch. I connected the yellow/black wire back at the plug at the power pack and I took the tape off the wire going to the kill switch and touched it to the ground on the switch box and it killed the engine. Im guessing that means the key switch is bad right?

 

[Bosunsmate]

Seems likely but connect it back up to the switch and see if it works, save yourself the price of a switch, Ive no idea why they cut and taped it unless the switch is shorting out, but some people rush in and do unnecessary things instead of investigating properly, maybe thats what they did.

You could also just rig up a push button and connect it between the black yellow and the switchbox and save you the cost of a switch.
Sounds like you dont have a safety lanyard cut out switch, they are very good to have in case you get thrown from the boat especially if the steerring snaps.
The safety switch works by grounding that black and yellow wire to ground if the pin is pulled. It is run in parallel to the key switch in the control box so either it or the key will kill the motor when grounded.

 

[jrtax]

I don't know why they did that. They cut it flush where the wire goes in and flush where is comes out. I called my local marine shop and they have a switch for around $20 so I think im just going to go buy one and try it. I really appreciate your help helping me get this figured out.

 

[jrtax]

I put a new switch in and it fixed it. Thanks a lot again for the help