nuetral safety and kill switch wiring

[redneckpunk]

I posted this in the general repair topics forum and while it received plenty of views, I got no suggestions on fixing it. Hoping maybe re-posting it under this section will provide some guidance.

Some quick background. Boat is a 1993 that has had an older merc o/b mounted on the stern. No serial # but believe its about a '77-'78 1150.

Problem is it appears the '93 throttle was used and the neutral safety switch was bypassed. I have 5 wires coming from throttle housing. 3 are for power trim. However, coming out the back of the housing are two blk wires with yellow stripes that have been cut. I traced the wires into the housing and found both go to the safety switch. I've checked the wiring harness from the motor to the counsel and dont see anywhere that those wires might tie in. The only other blk/ylw wires I have run between the ignition/key switch to the "kill switch".

So I guess my question is, how and where can I re-attach those safety switch wires in combo with the kill switch so there is no chance of an accidental starting in gear? I used the boat all last summer after purchasing it and never realized the issue as I have been around boats my entire life and the last thing I do before turning the key is check that its out of gear. But theres no guarantee that I will always be at the helm.

Thanks in advance
~RNP

 

[gm280]

Re: nuetral safety and kill switch wiring

Okay for starters regardless where you post your question, everybody can see it in the “What’s New” section of these iboat forums. But onto your problem(s). You have two different issues it seems. One is the neutral safety switch and the other is the kill switch. Usually the neutral safety switch is connected to the starter solenoid on the ground side. How that works is if you try to start the engine and it is NOT in the neutral position, the neutral switch will not be grounded to the chassis of the engine and allowing a completed circuit for the solenoid to switch power to the starter. The key switch will apply power to the starter solenoid but there won’t be a complete circuit to the return ground. The second issue is the kill switch. Your key switch when in the off position shorts the points or ignition module to ground therefore disabling any spark to the plugs. So you also connect those wires to the emergency kill switch as well. Then IF you are thrown from the pilot’s position or even overboard, the lanyard (which should be connected to your clothes or belt somehow) will pull the key out of the kill switch and short the ignition...stopping the engine from running. Usually those black/yellow wires are going to the points or ignition module and will be connected to the key switch and kill switch...but you should get a schematic diagram for your engine and verify those wires and their connections. Don’t buy a one manual fits all engine types either. Get a model, year, manufacture and HP specific shop manual and your troubles will be solved...

 

[glenn property of pam]

Re: nuetral safety and kill switch wiring

Wiring Color Codes for Mercury & Mariner Outboard Motors. this might come in handy

 

[redneckpunk]

Re: nuetral safety and kill switch wiring

gm, as a MOD on several boards, I am aware how the "whats new" section works, but I'm also aware that many people do not use it or will go only to the topics they are familiar with. And since I've gotten more from the 2 replies so far on here than I did over there, I'm going to assume it worked. I appreciate your explanation of both the kill switch and safety switch and their operations. Electrical has always been my weakness in comprehension. I will pull the cover off the motor and see if I can determine if the safety switch wires were also cut on that end, as I have already been able to determine from the controls back through the wiring harness the wires are missing. As for the kill switch, it works just fine, as I learned last summer when out on the lake I couldnt get spark to the motor after shutting it down minutes beforehand. After 10min of brainstorming and pulling my hair out I happen to see the lanyard laying on the floor. The PO had put in an adjustable captains chair and when in the furthest position back, when rotated inward, the hinges on the chair would catch the lanyard at the switch and pull it out. Boy did I feel stupid.

Glenn, thanks for the link. I found that one last year and book marked it when I had to rewire the ignition switch

 

[glenn property of pam]

Re: nuetral safety and kill switch wiring

im a little confussed but thats nothing new. The netrual safety switch will not be in the main harness but under the cowling on the engine harness the switch i think is on the negative side of the starter solinoid. look for the yellow with red stripe thats on the switch as there should be a wire with that color near the solinoid. if someone had a problem they may have unhooked the wire and just run a ground to the solinoid to get the engine to crank so when you plug it back in be prepared to find what ever problem they were trying to bypass

i hope this helps

 

[redneckpunk]

Re: nuetral safety and kill switch wiring

Perhaps my explanation wasnt thorough enough because I checked under the cowling and do have the ylw/red wires at the solinoid. My dilema though is the two wires at the remote throttle control unit have been cut and Im trying to determine where those two wires (both blk with yellow stripe) connect to.

~RNP

 

[glenn property of pam]

Re: nuetral safety and kill switch wiring

the boat has a modern shifter on a old motor so there is no key in the shifter but they ran 5 wires from the remote 3 for the trim and the last 2 are cut. If that is what you are saying then i guess the modern remote also had a kill switch built in that is no longer used as they proberly wired into the one on the dash at the same time they moved the key switch.
does the key start and stop the motor?
does the lanyard cord stop the motor when running?
does the engine crank over when in gear?

 

[Laddies]

Re: nuetral safety and kill switch wiring

Black/yellow are kill switch wires maybe this will help I can't understand which control you have for certain but the wiring is a similar on most controls.

 

[Silvertip]

Re: nuetral safety and kill switch wiring

There are two "M" terminals on the ignition switch. When the ignition is turned off, those two terminals are connected which kills the ignition. The kill switch (what you are calling the "safety switch") are connected in parallel across these two terminals. Therefore, when the kill switch lanyard is pulled, the two "M" terminals are connected just as they would be if you you turned the key off.

 

[redneckpunk]

Re: nuetral safety and kill switch wiring

the boat has a modern shifter on a old motor so there is no key in the shifter but they ran 5 wires from the remote 3 for the trim and the last 2 are cut. If that is what you are saying then i guess the modern remote also had a kill switch built in that is no longer used as they proberly wired into the one on the dash at the same time they moved the key switch.
does the key start and stop the motor?
does the lanyard cord stop the motor when running?
does the engine crank over when in gear?

Yes, the key, which is on the dash does start and stop the motor.
Yes, the lanyard cord does stop the motor.
Yes, the engine does crank over in gear <<~~~~~problem Im trying to resolve.

Key/ignition with built in choke are dash mounted. kill switch with lanyard is mounted in side wall behind throttle control unit.

I think I'm going to pull the key switch out of dash to compare wires with whats hooked to the kill switch with lanyard. I'm hoping colors will match but not too optimistic as many wires have been changed/spliced/etc with unmatching colors. I assume, that if I tie the wires from the Neutral safety switch into these, in line, it should solve the problem

 

[glenn property of pam]

Re: nuetral safety and kill switch wiring

Yes, the key, which is on the dash does start and stop the motor.
Yes, the lanyard cord does stop the motor.
Yes, the engine does crank over in gear <<~~~~~problem Im trying to resolve.

Key/ignition with built in choke are dash mounted. kill switch with lanyard is mounted in side wall behind throttle control unit.

I think I'm going to pull the key switch out of dash to compare wires with whats hooked to the kill switch with lanyard. I'm hoping colors will match but not too optimistic as many wires have been changed/spliced/etc with unmatching colors. I assume, that if I tie the wires from the Neutral safety switch into these, in line, it should solve the problem

ok thats simple then the netrual safety on your motor is not under the cowling on the motor but was proberly inside the remote throttle. you will have to open the throttle and find the micro switch then put it in line with the starter solinoid wire from the key switch. laddies post #8 shows it as part c