Installing a deadmans switch, need help.

Jimmy70

Cadet
Joined
Jul 6, 2007
Messages
29
Hi All
I have a 40hp Mercury engine and have it on a speed boat and almost dumped me the other day doing 50mph. So decided to install a deadmans switch just in case.
It is a standard Mercury ignition key switch that I have on the boat. The deadmans switch that I bought is like a two pole switch, when the button for the switch is pushed in then those two leads make contact, when open the open the ciricut and then when the button is out then the other two make contact but the other one opens like I think it should to break the ciricut and stop the engine. I have put the switch on all of the wires for a breaker but makes no difference the engine keeps running once I pull the switch to the out postion and break that ciricut.
So if anyone can tell me how to correctly install this thing I would appreciate it.
Jimmy
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: Installing a deadmans switch, need help.

We kinda need to know what 40 you have. How many cylinders would help. 4-stroke or 2-stroke would help. Serial number would help. But no matter which, you need to connect the switch to the M terminals of the ignition switch if you have a switch with Ms. The switch would need to be open when the tether is in place and make contact when the tether is pulled. On newer models, those wires are black and black with a yellow stripe. On older models, black and pink(ish). I'm betting on the black and pink because most of the newer ones would already have one.
 

Jimmy70

Cadet
Joined
Jul 6, 2007
Messages
29
Re: Installing a deadmans switch, need help.

Okay it is a 2 cyl. 2 stroke, 5991908 serial number.
The switch that I bought is a teleflex, MP40970 with a safety lanyard. The black with yellow is the kill wires which I installed the switch to those wires going thru the safety switch but when I pulled the lanyard from the switch the engine kept on running and then when I pushed the switch back in then it killed the engine. Don't make sense to me but if you can explain please do.
Thanks
Jimmy
Maybe I did not hook the wires to the correct terminals on the safety switch and was thinking backwards on it.
 
Top