Shift Interrupt Switch

[PeteK]

Hello to all,

Learning as I go and could use some guidance. Not sure about shift interrupt/neutral lock etc. Have two switches that appear to be shift interrupts. One is on the valve cover and looks to be incomplete. The other is on the inside transom plate/shift plate and is electrically disconnected. Looks to me like the valve cover switch was added to replace the transom switch which was abandoned.

Engine is Mercruiser 3.0 circa 1987

Sterndrive is MC- 1

I've got wiring diagrams and have a basic understanding of the concept but need to fill in some big gaps like should't there be a lever arm and also a cable attached on the valve cover switch. Also where does the cable come from/to etc.

Not asking for a step by step hand hold but a hint or a past thread would be a big help.

Thank you fellow boaters

PeteK

 

[Bt Doctur]

need a wider pic showing the cables and the other shift plate
http://www.boatfix.com/merc/Techbk/94/94hsa2.pdf

 

[PeteK]

Bt Doctur,

Thanks for the link. Better pics will follow.

 

[PeteK]

Did a little more research. Looks to me like both the old transom-plate shift interrupt switch and the newer valve cover-mount style are both installed. The valve cover-mount is wired in but not linked by cable. The transom mount shift interrupt (old style) is in place but not connected electrically. I need to make sure one or the other is serviceable. Shift cable is set up on the transom shift plate and works - on muffs shifts forward/neutral/reverse no problem. No test under load though.

I understand the old style shift interrupt switch is obsolete so am thinking of making an effort to use the valve cover mount mechanism. Not sure what is involved.

 

[Bt Doctur]

such a mismash of parts . you need the switch to have the drive come out of gear IN THE WATER with a load on the prop.So locate a complete valve cover control to switch over to.and put the cables there. If you have a points system ,the switch grounds the neg side of the coil.

 

[Rick Stephens]

I'll bet this boat was re-engined at some point with an engine that had the valve cover switch.

 

[PeteK]

This is not the original engine.

 

[Bt Doctur]

You can use any newer shift plate, just get one thats complete and mount it someway/somwhow