shift interrupt switch system

[grarrsmi]

Hey guys, I had the engine out of my boat last winter to do some work. Put back in and could not get a spark anywhere. I printed off a check list to try to figure out why it wasn't sparking (don't remember where I got the check list from). After going though all the test it was the tachometer that was bad so it would not let it spark. Instructions said to disconnect the grey wire on the coil and if it starts it is the Tach or the wiring to the Tach. So I left the grey wire off thinking I could just get a new Tach later. But than I started to have problems with the shifting into neutral. Was thinking I was having problem with the Shift interrupt switch. After looking at the wiring diagrams for my boat, I have to have that switch hooked to the - on the coil. It comes off the switch as white/green and ties into the grey wire to the coil. Can I just run a wire from the switch to the - on the coil to make it work for now. Don't really want to buy a tach right now. I am not cheap, I just want to get a new gauge set next winter and not now. Want to replace all because they are getting old and dirty on the back.

Here is what I have-
Mercruiser 91 3.0 Alpha 1
Transom# OD418299
Drive# OD454968

 

[Reel Poor]

Re: shift interrupt switch system

The simple answer is yes but you will have to disconnect the white/green (that's connected to the tach lead) from the shift interrupter terminal block also or your tach will be back in-line.

 

[grarrsmi]

Re: shift interrupt switch system

The simple answer is yes but you will have to disconnect the white/green (that's connected to the tach lead) from the shift interrupter terminal block also or your tach will be back in-line.

Real poor, Maybe you can explain it a little better of why I have to disconnect the green/white wire. As soon as I do that than I will be back to no Shift interrupt switch. Am I right? If so than my only option is to get a new Tach.

 

[grarrsmi]

Re: shift interrupt switch system

Oh wait, I think I know what your saying. Disconnect the green/white wire from block and run a new wire from the block to the coil neg.

 

[Reel Poor]

Re: shift interrupt switch system

Can I just run a wire from the switch to the - on the coil to make it work for now.

The switch has two wires on it, a black and a white/green. These two wire are connected to the wiring harness at a terminal block. Disconnect the harness side, white/green wire, from the terminal block and install your temporary wire at this connection terminal.
If you don't disconnect the harness side white/green wire when connecting your temporary wire it will just back feed to the tach.

 

[Reel Poor]

Re: shift interrupt switch system

Oh wait, I think I know what your saying. Disconnect the green/white wire from block and run a new wire from the block to the coil neg.

Correct!!