I posted this before but didn't find the answers I was looking for

[leesumm]

I have a 1977 70 HP Johnson (new to me). When I got it the guy said it started "not shutting off with the key" I posted here for some help and ordered a manual. But, the manual don't help and no answers got the solutions. I put in a new key switch , traced the wireing down and cant find an open any where. It has the "red plug" on the engine and the black and yellow wire from the switch side in the plug doesn't go to a wire on the engine side. Now I am confused and can't find the right diagram for what I have. Can anyone help me.

 

[Bob_VT]

Re: I posted this before but didn't find the answers I was looking for

First I looked at your old posts and that was not posted before. Without a wiring diagram of your motor to examine which is in the manual or the motor in front of me I have no idea.

 

[schematic]

Re: I posted this before but didn't find the answers I was looking for

find the kill wire on the pack. Ground it while engine running. if it doesn't shut off, replace the pack

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

ok, I think I saw this check on another forum. I havent got that far yet and the pack if I know for sure what it is looks very new and there was an old one in the "glove box" on the boat when I got it , so I was assuming it had been replaced too.

 

[schematic]

Re: I posted this before but didn't find the answers I was looking for

never assume

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

The plug on the engine harness is red, is the plug on the control box harness red also, they have to match.
Here is a schematic that should match your engine.
Post your model number please?

http://maxrules.com/graphics/omc/wiring/78-84_3-CYL_EL.jpg

 

[F_R]

Re: I posted this before but didn't find the answers I was looking for

Be very careful not to connect any voltage source to the black/yellow kill wire, or you will blow yet another powerpack.

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

I havent got to the point of grounding the kill wire on the power box yet. I took the harness off and checked continuity from the box to the switch. And couldn't find a broken wire. What does get me tho, I have a 100 continuity between the ends of the wires on the engine side of the black/yellow wire. But when I ground for continuity between the black/yellow and the engine itself it wont ground completely at 200 ohms on my meter. It still shows about 14.5 resistance on the 200 ohm side. I am not much of a electrician or able to read the schematics that well but it don't look right.

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

find the kill wire on the pack. Ground it while engine running. if it doesn't shut off, replace the pack

Ok, did the continuity checks on the ground wire or kill wire which ever it may be. It shows full continuity between the end of the wires and thru the plug to the switch. But checking the continuity on ground on the engine it shows a break. I started the engine and grounded the wire as told in previous post and the engine died.
Now back to the original post that started this post. I start the engine. It runs fine, the switch wont kill the engine. I have checked all wires and terminals. Replaced the switch, shorted the kill wire on the power pack to ground and the engine shuts off.
When I traded for the boat and motor the guy said the last time he had it out and couldn't shut the engine off and had to choke it to kill it. So now where do I go. I have done everything I can find in the books and read on the forum posts and back to the original problem of not being able to shut the engine off without using the choke.

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

Could you read post#5 and ansewer the questions?

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

#5 says "never assume" which I guess refers to assuming the power pack was new, since I had an old one in the boat when I cleaned it out from the previous owner.
Yes the plug on the engine is red. the plug from the switch on the boat side is red they match like peas in a pod. I can't any other colors to match up or guess that is wrong in the wireing harness and I can't seem to find any broken wires.

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

OK, you have checked and you have continuity on the black/yellow wire from the switch to the point where you grounded it to the engine to kill the engine. If you ground the black/yellow wire at the engine it will kill the engine.
With the engine running, use a jumper wire and ground the terminal on the key switch that the black/yellow wire attaches to. (be careful, you can get a shock off of the wire if you are not careful) If the engine quits that means you have a complete circut in the black/yellow wire. If that works you either have a switch that is not grounding the black/yellow wire in the off position or the ground wire on the switch is not grounded. You might check the continuity on the ground wire on the switch.

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

Ok, Daviet will try that . Now this is a stupid question I think , but does the control box on a out board have to be grounded to the battery itself or does it pick up a ground thru the wiring system thru the motor? Like on a motor vehicle most anything metal is a ground but since the body on this boat is fiberglass I am not sure how the ground would come in the control box.

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

The control box is grounded through the wiring harness back to the engine, it does not go directly to the battery.

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

ok, I took the control box apart again. the black ground wire is checking good continuity between the case and the key terminal. Shorting the black / yellow wire terminal the engine died. The switch is new and doing the same thing as the old switch that was in it. Is it possible to get a bad switch new ? When I replaced the switch I did it the dummy way. One wire at a time so I wouldn't confuse wires. I just checked the wires to make sure they were correct when I changed the switch and the color code corresponds to the schematics I have found. While in the control box , I found a bad neutral start switch. The switch itself is good but the plunger in the switch is broken and bent. And of course all parts I can find on the internet its obsolete. Will this switch keep the key from killing the engine? Also would it be possible join the two wires together on the switch and bypass it? I know this will allow to start in gear.

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

OK, you have confirmed the black/yellow wire going back to the engine is a complete circut, if grounded it will kill the engine.
You confirmed that the ground is complete from the switch to the control bx, what about from the control box back to the engine?
Look at the schematic in post #6, you will see a ground wire coming out of the red plug and grounding at the ground for the starter solenoid. Do you have a complete circut to that grounding point?
The neutral safty switch will not stop the engine from being turned off, it is only used for the starting circut.
You can bypass the switch, but as you said, it will start in gear and can be a big safty concern if someone else is running the boat.

 

[durban]

Re: I posted this before but didn't find the answers I was looking for

best thing to do is take the fly wheel off & lets see what system you have under there , i have seen guys sell motors where they have changed electrical parts around , they advertise the motor saying this & that about model no,s etc ,me being knowledge d i catch them out ,cheers

 

[leesumm]

Re: I posted this before but didn't find the answers I was looking for

Ok, been back out at it again today, for the hell of it I went back and checked and double checked all connections and wires plus the continuity on all wires. I pulled the control box apart and rechecked all that . Unplugged the red plug and checked continuity on the ground wire, nothing. I hooked another wire outside of the cable and ran it to the plug and spliced in and connected the plug back. Started up and ran fine, the KEY EVEN SHUT THE MOTOR OFF !!!!!!!!. Halleuhaaaaa. So I took the control cable harness apart and ran a new ground wire in the cable and put it all back together and hooked everything back up. Ran like a 30 year old Singer sewing machine. Maybe even better than before the new wire job.
I have to thank the help of Daviet, thank you thank you and thank you. Did I say THANK YOU ?
I had combed the internet and posted and read and looked and about everything was in order according to the reading. I just never thought the cable might have a bad wire in it. It still had the original casing on it and never been cut, bent ?? or other wise looked damaged but evidently the wire was broke.

 

[Daviet]

Re: I posted this before but didn't find the answers I was looking for

You're welcome.
I knew you would figure it out, sometimes it takes a little more digging to find a problem.
Happy boating.