Not going into neutral .

[Lager]

Im new to Io"s.
Second time on the water with this 89 3.0 today and I noticed something.
The out drive will not go into neutral even tho the throttle is pulled back to the neutral position.
I have to force ably yank the shifter to reverse, then again bang the shifter into neutral position to get to stay out of gear.
There is a roller mounted switch attached to my shifter mechanism attached to the top of my engine.Noticed the roller is not centered in the groove as Im guessing it should be.Its actually riding well up out of the groove and its not adjustable. From what I have been reading this is an interrupter switch that kills the ignition momentarily to reduce the load on the transmission to allow it to shift out of gear.
I dont know how this switch works, I can tell you that if I disconnect it with the engine running, it still stays running. Its obviously depressed at all times right now.
The boat shifts normally into forward and reverse when out of the water, its only when there is a load on the prop.
Does the switch being out of position mean the shift cables are set incorrectly ?If so, why does the boat hit all its correct shift points on land or in the water.
Will disconnecting the switch and the engine still running mean the switch is bad?
Many Thanks to anyone that can help me here.

 

[LawHungLow]

Re: Not going into neutral .

Sounds like a wire is disconnected from the switch. Or the switch isnt engaging completely to kill the engine. Also, yes your shift cable is out of whack if its constantly engaged. The switch is open until it is depressed, then it is closed and grounds it out. Disconnecting the switch isn't going to do anything. Try to press it in more by hand while it is running to see if it kills it. If it does, then you might be able to just bend the lever to the appropriate spot so that it makes a connection when the shift mechanism engages it. You could also take the switch out and test it with an ohmeter to see if it makes contact when you press it in all the way.

 

[thumpar]

Re: Not going into neutral .

A bad lower shift cable will make it look like the shift interrupt switch is not working. The reason it works on land is because there is no load on the prop. That is why the switch is meant to kill the engine quickly to get it out of gear while in the water.

 

[ktbarrentine]

Re: Not going into neutral .

I dont know how this switch works, I can tell you that if I disconnect it with the engine running, it still stays running. Its obviously depressed at all times right now.

Here is a great tutorial on this switch from the late, great Don S.

http://forums.iboats.com/mercruiser...-how-shift-interrupt-system-works-288089.html

 

[Lager]

Re: Not going into neutral .

Interesting info.
Can tell you what I have learned since, if I remove the switch and check it with an ohm meter. Its working correctly.
But no matter how I activate the removed switch, it will not kill the the motor.
Then I remembered that added another tachometer and removed the original wire of the neg term of the coil since I first ran the boat.
So, I reconnected it and now the switch will kill the engine when activated.
Obviously its tied in somehow to the original tach wiring.
Going to throw the boat back into the water tomorrow and see how it works now.

 

[LawHungLow]

Re: Not going into neutral .

Is the shift mechanism still holding the switch closed? If it is, I wouldn't waste time taking it to the water until that's fixed. From the original post, you said the switch stays engaged all the time while in the water - which means your shift cable could be going bad or it's way out of adjustment. My bet is if you take it to water, you'll have a hard time keeping it running because that switch will be engaged.

What's the history from the previous owner? Was the shift cable replaced? (Possibly not adjusted properly) I've came across this before where it wouldn't go to reverse... Simple move on the lower shift cable took care of it.

 

[Lager]

Re: Not going into neutral .

Strangely enough, it works perfectly now. The wiring for the ignition kill has got to be tied into the original tachometer. Once I connected the original tach wire it now works great. Im not messing with the cables, it goes into forward and reverse slick as a whistle.
I DO want to thank eveyone for your responses and hopefully, this might help anyone else.