Re: shift interrupt switch



There is a piece of metal that pivots where the shift cable from the control
box attaches and also the cable to the lower unit attaches as well as the
linkage to the carb. This is where the shift interrupter is located. It is
a common leaf spring micro switch. It temporarily kills the engine during
shifting to release the pressure on the gears.

Usually the best solution is to replace both of the cables and the shift
cable bellows. The parts are not excessively expensive but you need a
special tool to install the threaded end on the lower unit end, or you can
make one by splitting a 3/16 slit in a deep socket so you can slip the cable
into the socket.

You did not state, but I'm presuming you have a Merk.

Don Dando


"Fred" <fredmere@xxxxxxxxxx> wrote in message
news:pan.2005.10.04.23.56.53.872000@xxxxxxxxxxxxx
> I've got a '85 Mercruiser 3.7l 170.
>
> In the last two trips, I've had trouble out on the water shifting from
> forward->neutral->reverse and vice versa. There really isn't a neutral,
> which makes docking a challenge, you can imagine.
>
> There's a good bit of resistence at the remote control where I fight it in
> and out of gear... the resistence may grow as the engine warms (or I may
> just tire).
>
> After the first time, I ran it on muffs in the yard for more than an hour
> and the problem seemed to go away, which prompted me to go out the second
> time. So maybe there's something to the added pressure on the prop, I
> dunno.
>
> I figure the problem is either electrical (shift interrupt switch) or
> mechanical (shift cables, levers, etc.). I'm inclined to attempt to debug
> the electrical portion before taking it to a mechanic. I read in my
> Clymer's manual about the shift interrupt switch and saw a wiring diagram
> of it, but for the life of me, I can't find it when I'm looking down on
> the engine.
>
> Does anyone have a helpful photo or advice?
>


.



Relevant Pages

  • Re: Mercruiser i/o will not go into neutral
    ... > All correct except the shift engine kill switch SHOULD engage if there is ... but when the control cable and lower shift cable are in good ... > because the engine is running faster than the prop. ... or misadjusted cables, or a simulated shift load caused by resistance ...
    (rec.boats)
  • Re: Mercruiser i/o will not go into neutral
    ... >> All correct except the shift engine kill switch SHOULD engage if there is ... >> because the engine is running faster than the prop. ... Bending the shift cables by having the outdrive at extreme angles ...
    (rec.boats)
  • Re: Mercruiser i/o will not go into neutral
    ... >>> All correct except the shift engine kill switch SHOULD engage if there is ... >>> because the engine is running faster than the prop. ... Bending the shift cables by having the outdrive at extreme angles ...
    (rec.boats)
  • Re: Campy/Shimano rear derailleur spring differences?
    ... Having a $5000 bike and not replacing your $50 cables regularly seems like a waste to me. ... And the shifter feel is pretty poor in Campy ... shifters, whereas Shimano's 10-speed shifters are so ... it's a pleasure to shift. ...
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  • Re: Mercruiser i/o will not go into neutral
    ... The shift bellow doesn't seal water out of the cable. ... cables need adjusting. ... The purpose of the interrupt ...
    (rec.boats)