engine kill switch?

[ETsubchief]

I have a 120 mercruiser. On top of the engine, attached to the throttle cables there is a plastic V, that a microswitch hits on. If the switch rolls up on the top of the v, it kills the engine. Normally i dont have a problem, but occasionally it happens.
So what is the purpose of this switch, and what adjustments can i make to stop this from happening.
I would love to post a pic, but guess i am too retarded to figure it out with my tablet:huh:

Thanks,
Mike

 

[src]

It sounds like the neutral safety switch, which prevents the engine from starting unless it is neutral. If it is out of adjustment, it can kill the engine during operation. I don't have any adjustment information for you, but hopefully that will put in on the right track.

 

[ETsubchief]

I was thinking the same thing, but havent found anything yet about it.
I havent even found pics yet

 

[Westie]

Neutral safety switch will be right on the throttle handle.
The switch that you are looking at is the shift interrupter switch. It momentarily kills the engine when shifting into gear.

 

[ETsubchief]

Ok. Reading many different posts, and how to's it seems that i need to adjust my shift cables. I also have been having some grinding when shifting from fwd to reverse, and vice versa.
Guess thatsva project for tomorrow.

 

[ETsubchief]

Made adjustments to the shift cable, prop is fully engaged at proper points, but still getting some grinding when going into fwd and reverse. Doing some more reading it looks like this might be normal if boat is outof water on muffs? Boat has always done this since bought her, doesnt mean its correct.
Now, the interrupter switch is not engaging. I can manually shut the switch and kill the engine, but when shifting, the V bracket doesnt move enough to activate the switch. Any thoughts?

 

[KC_Sundancer]

Made adjustments to the shift cable, prop is fully engaged at proper points, but still getting some grinding when going into fwd and reverse. Doing some more reading it looks like this might be normal if boat is out of water on muffs? Boat has always done this since bought her, doesnt mean its correct.
Now, the interrupter switch is not engaging. I can manually shut the switch and kill the engine, but when shifting, the V bracket doesnt move enough to activate the switch. Any thoughts?

That switch only creates a momentary activation (kill of the engine) to release pressure on the drive gears so they will shift. It's probably activating just not noticeable.

As far as a grinding noise (a sound like trying to put a car in gear without using the clutch) is normal with alpha drives if you are slowly moving the throttle past the shift points.
The engage/disengage movement of the throttle past the shift points should not be done with a very slow movement of the throttle. You have to get a feel for it as you don't want to shift and then quickly accelerate by mistake.

 

[ETsubchief]

Took her out today, at first she wouldnt go into neutral unless i shifted past neutral.
Made more adjustments, finally got it to shift right, with very minimul grinding, if any.
Just need to play with arm on switch, i think its closing abit too soon. Engine almost dies, but i think i can tweek it abit more:grin:
Thanks for everones help. You all assured me the path i was going was on the good Side:thumbsup: