Bypass the neutral safety switch - 1978 Merc

[samm835]

Is there a way to bypass the neutral safety switch on a 1978 90hp Merc? I know that it is for safetly.....by it is only a temporary fix. Thanks for any help.

 

[CV16]

Re: Bypass the neutral safety switch - 1978 Merc

I had to disconnect mine on my old boat. All I did was take apart the control box and remove the switch. It took 3 days to get the new switch, and it was an easy fix. Just pay attention to how it all comes apart. I lost the little detent roller when I did mine. That would also be a good time to lube it up in there.

 

[samm835]

Re: Bypass the neutral safety switch - 1978 Merc

Yah I had my controls apart, but I wasn't sure if I disconnected it that the motor would start. I know on some safety switches if they are removed/disconnected and nothing is put in its place it defaults to "not working" and the motor wont start. So if I understand correctly, all I should need to do is disconnect the wires and my motor should run correct? Thanks for your help.

 

[CV16]

Re: Bypass the neutral safety switch - 1978 Merc

Mine did, but it's a 1973 1500. Just make sure you're in neutral when you start it.


EDIT: Not sure what your problem is, but I also had to disconnect the mercury switch on a different motor to get it to fire. On mine, it was located on the back starboard side of the motor. Two wires to disconnect, all it does is make it to where it won't start if the motor is trimmed up too high.

 

[Moody Blue]

Re: Bypass the neutral safety switch - 1978 Merc

I know on some safety switches if they are removed/disconnected and nothing is put in its place it defaults to "not working" and the motor wont start. So if I understand correctly, all I should need to do is disconnect the wires and my motor should run correct? Thanks for your help.

Negative Samm. If you simply disconnect that safety switch, you will not be able to start your motor. Take a look at a wiring diagram here to understand how they are connected

http://www.maxrules.com/oldmercs/Wiring/1966ona/31.jpg

To bypass the switch (I never told you to do so because it's a REALLY BAD IDEA) you need to connect together the two wires that are disconnected from the safety switch.

 

[Moody Blue]

Re: Bypass the neutral safety switch - 1978 Merc

Mine did, but it's a 1973 1500. Just make sure you're in neutral when you start it.

Not sure how thats possible CV16. The safety switch provides power to the starter solenoid ONLY when the switch is closed (controller in neutral). The normal state of the switch is open circuit, so if you try to start in gear, no power is delivered to the starter solenoid.

If you simply remove the switch, there is no longer any continuity between the ignition switch and the starter solenoid.

 

[CV16]

Re: Bypass the neutral safety switch - 1978 Merc

It's been a dozen years or so. I guess I may have twisted the wires together, but I really don't think I did.

 

[Chris1956]

Re: Bypass the neutral safety switch - 1978 Merc

The mercury switch located near the ign coil is to kill the motor if it over trims. The neutral safety switch in in the MerControl. You need to connect the two wires together.