Shift Interruprer Switch

[Firebaby]

Can anyone tell me if my boat has a shift interrupter switch. 1985 Four Winns I/O with 190 Mercruiser and Alpha 1 unit. It dies when shifting in and out of gear and I have heard 2 different stories. One that it might be a shift interrupter and another that my boat is too old for one. If thats the case then what? Thanks.

 

[Uraijit]

Re: Shift Interruprer Switch

Your boat should have a shift interrupter. Boats MUCH older than yours have 'em.

It's mounted on the shift plate that connects the upper and lower cables.

Do you have manuals for your engine and drive?

 

[APPALOOSA2]

Re: Shift Interruprer Switch

You do have a switch but if you were shifting fine and this started I would say your shift cable is bad. The cable that goes to your lower unit. Cables don't go out of adjustment all of a sudden.

 

[chiefalen]

Re: Shift Interruprer Switch

Yea they do, they stretch. Try adjusting but probably need a cable.

The switch could be sticking. You could disconnect the switch and see if shifts better.

Thats what i would do before messing with the cable. Do it out in open water.

Good luck!

 

[Firebaby]

Re: Shift Interruprer Switch

It sounds like I have one then. I'm not at all mechanically inclined, so this has been an adventure for me. I will take the boat out and try to see if I can correct the issue using the methods suggested and inspecting the cables, but first I have to charge the battery (I learned this this morning at the dock). I'll let everyone know and thank you.

 

[ziggy]

Re: Shift Interruprer Switch

You could disconnect the switch and see if shifts better.

if ya do this, it won't shift out of gear at all if it's running. ie, fwd to neutral, rev to neutral.. it will shift from neutral to fwd or rev. w/o the interupt switch as the shift interupt switch don't do anything when making this shift...

the shift interrupts function is to momentarily turn the engine off. right when your shifting from fwd to neu. and rev. to neu. the engine needs to be off to shift as the gears that are being disengaged are undercut. meaning the more pressure on them, the more they want to lock together. the momentary turning off of the engine, via the shift interrupt switch is what allows you to get the gears out of mesh.....

to see if the cable is bad, remove the end on the shift plate and shift it (run the cable in and out) with your fingers. when in fwd. the prop will lock ccw, when in rev. the prop will lock cw. the cable should move nice and freely if it's serviceable....

lower shift cables seem to be a common replacement item on older boats.....

to play with your boat mechanically, you really need a service manual. it's a must have item.... get yours over here.....http://forums.iboats.com/showthread.php?t=251571

 

[allingeneral]

Re: Shift Interruprer Switch

I have had problems with my shift interrupter switch and I have always been able to correct it by spraying it with a little WD-40. My problems were due to the switch sticking as I shifted out of gear and the engine would die. A little WD-40 does the trick for me.

 

[Firebaby]

Re: Shift Interruprer Switch

I hope that all it needs is a little lube, I sprayed it at the dock but my battery was dead so I haven't been able to test that attempt to fix yet. It sat for three years prior to this summer when I bought it. It died some at first, but then I had the water pump go bad and I overheated. I fixed that but have only had it on the water for a few minutes to test the pump fix. That is when I noticed an increase in the number of times it would die. With work and the weather forcast, it appears I won't make it out on the river to test it for a couple of weeks. I'll let you all know, and again thanks for the help.

 

[Firebaby]

Re: Shift Interruprer Switch

I also posted a question about my swim deck, I have a trolling plate, which did me no good when the motor went out. My brother offered me the use of his older trolling motor, but will the swim deck handle the stress if I mount to it and what would be the best way to do so (hopefully without drilling holes). This may save my rear in the event of future mechanical problems.

 

[Don S]

Re: Shift Interruprer Switch

Your shift cable is probably dead, and no amount of spraying it with anything is going to fix it. It needs replaced.
Sounds like the engine and drive both may be in need of some long overdue preventive maintenance.

 

[Bondo]

Re: Shift Interruprer Switch

Your shift cable is probably dead, and no amount of spraying it with anything is going to fix it. It needs to be replaced.
Sounds like the engine and drive both may be in need of some long overdue preventive maintenance.

Ayuh,.... No Doubt......

Btw,....Allingeneral,..... You need a New cable too.....

 

[clerihew82]

Re: Shift Interruprer Switch

Ayuh,.... No Doubt......

Btw,....Allingeneral,..... You need a New cable too.....

Bondo can you ever post without saying "Ayuh,....". And what does that even mean????

 

[chiefalen]

Re: Shift Interruprer Switch

Just curious what rpm are you at idle? When the boat is in the water.

Not saying it ain't the cable.

Have you guys ever tried to disconnect your shift switch to see what the boat really does?

 

[Firebaby]

Re: Shift Interruprer Switch

You know, I am not sure.......I doesn't sound like it is fast. Is there something your thinking that I might look at when I take it out?

 

[Bondo]

Re: Shift Interruprer Switch

Bondo can you ever post without saying "Ayuh,....". And what does that even mean????

Ayuh,.... I suppose I could,....

Btw,.... Google is your Friend......

 

[chiefalen]

Re: Shift Interruprer Switch

Should idle in the water 650-700 in gear. How big is that boat. How many hp is the trolling motor?

To fast a idle you won't be able to shift. Whats the tach say even though they are notorious for being wrong.

Look you have don s and bondo telling you it's the shift cable lower. My bet thats what it is.

If the switch ain't sticking thats what it is. Verify the switch first.

Good luck!

 

[Don S]

Re: Shift Interruprer Switch

To fast a idle you won't be able to shift.

Unlike an OMC with the fancy ESA module, if a Mercruiser shift interrupt switch is engaged at 5000 rpm, the engine will die.

 

[Firebaby]

Re: Shift Interruprer Switch

The boat is a 19.5 foot Four Winns Horizon Cuddy Cabin. I'm not sure about the size of the trolling motor yet because I have not been able to get ahold of my brother to find out. He had it on an older model boat about 16 or 17 foot, so I'm sure it will move the boat, I'm just afraid of what might happen to the swim deck as it is fiberglass and rather large.
I will check the idle speed when we check out the boat, but I am inclined to believe it's that switch or a cable.....hope not and I will definately be sure to check all possabilities. If I have to replace one or more of these items, can I do it myself and how bad will my pocket book suffer?

 

[achris]

Re: Shift Interruprer Switch

Many people in the past have decided that the problem is the switch, disconnected it.... only to find sometime down the track that all the pointy, shiny bits in the leg have become round... Disconnect the switch at your peril.

1. Get the right OEM manual.
2. Do the right diagnosis.
3. FIX THE REAL PROBLEM!!!...

So many people on this thread have told you that you have a bad shift cable... Why are you ignoring them? Don't just keep taking the boat out, in hope that the problem will just go away, or that talking about it here will frighten it into not doing it anymore. If you are not mechanically inclined then take it to a shop. Get it fixed now and you could save yourself thousands in the future.

Remember the old adage : an ounce of prevention is worth a pound of cure.

Chris.............

 

[Uraijit]

Re: Shift Interruprer Switch

Bondo can you ever post without saying "Ayuh,....". And what does that even mean????

Ayuh,.... I don't think he can.

It's a funny way of saying "yeah". Try saying "yeah" while eliminating the Y-sound, and trying to make it sound like fingernails on a chalk board, and you've got it.

It's a North-East thing. Vermont, Main, and Canuks in that little corner of the word say it.

Don't know if it's a laziness thing, a blatant attempt at being obnoxious, or too much salt spray in their nostrils, but they just can't seem to help themselves...

I just blame it on bad parenting...

The comma, followed by a 5-period-or-more-ellipsis part is his own invention, I believe.........