3.0 Merc Shifting Issue

[meder24]

I had my '87 Thompson with the 3.0L Merc and Alpha 1 Gen 1 out for the first time yesterday. During the process, I began to have intermittent issues where I could not shift back into neutral from either forward or reverse. Some times I could not disengage from drive while other times everything worked normally. There was no consistent situation I could get the problem to replicate. It would work fine and then not work correctly both while moving and not.

This led me to believe I am having either shift cable issues or my interrupt switch is going or has gone bad.
I just verified my shift cable adjustments a few weeks ago getting ready for the season so i do not suspect those to be the issue. I did suspect maybe my throttle control is going bad but what I did next caused me to think that may not be the case.

While on the water (under load) and at home on the trailer, I tested the interrupt switch by pushing the lever to make contact. Neither time did the engine cut out while I had the lever pressed. If the switch were working, I would assume i would have had some reaction in one of the two cases.
I have not taken the switch out to test for continuity yet, but should I have had some sort of stall action in either case?

Any input would be appreciated.

 

[Bt Doctur]

no need to remove it , just test it.needs a ground and needs to be connected to the coil

 

[meder24]

Thank you.
I am also going to try and clean up the contacts a bit too. It seems strange the switch would just stop working so randomly.

 

[Fishermark]

Switches do go bad. And yes, if you engage your switch, the engine should die.

 

[meder24]

Good to know.
Should the engine die regardless of whether it is under load in the water or sitting on a trailer with muffs?

 

[Bt Doctur]

when manually activated the motor should stumble/stall. only activates in the water ,coming out of gear
If on land, lower shift cable is bad

 

[meder24]

Good info. I get no stumble or stall whether in the water or not when manually activated.

 

[Bt Doctur]

then the switch is bad or not connected

 

[meder24]

Upon closer examination, my switch is not bad. It turns out the ground wire was not making contact with the ring terminal type connector it was mated with. I fixed the wiring issue just to find out the engine stalls when shifting to reverse.
Looks like a new shift cable for me.

 

[meder24]

Never Mind, going to replace the gasket.

 

[Fishermark]

Never Mind, going to replace the gasket.

 

[meder24]

Sorry,

I asked a questions earlier about using the new gasket I partially tore during installation. I didn't realize I erased the entire post. Sorry.