Re: Mercruiser i/o will not go into neutral

This has been a most interesting thread. Thanks!





On Tue, 24 Jan 2006 09:29:35 -0500, "Jeff Rigby" <jeffg212@xxxxxxxxxxx>
wrote:

>
>"markvictor" <coppercollar1@xxxxxxxxxx> wrote in message
>news:1138084542.168089.127580@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>> Jeff Rigby wrote:
>>
>>> All correct except the shift engine kill switch SHOULD engage if there is
>>> any resistance disengaging from reverse or forward into neutral.
>>
>> I agree, but when the control cable and lower shift cable are in good
>> condition, and adjusted correctly, the only way the clutch is "loaded",
>> is essentially when underway above nominal idle,or excessive rpms prior
>> to shifting, thus keeping tension on the clutch dogs.
>>
>>
>>
>> if the cables are out of adjustment, When trying to engage
>> from neutral, if the rpm's are too high from premature throttle
>> opening,the clutch will resist and the interrupt switch is actuated.
>> When in gear,if the throttle is not closed and rhe RPM's are ,once
>> again, higher than nominal idle speed, the clutch dogs resist
>> disengagement, again tripping the interrupt switch...
>
>>> This resistance (if shift cable is good) comes from the dog gear not
>>> disengaging
>>> because the engine is running faster than the prop. The kill switch
>>> engages
>>> and the motor slows relative to the prop and the gear can disengage.
>>
>>
>> If the engine is running, and the drive is engaged (in gear) It is
>> absolutely impossible for the engine to EVER run slower than the
>> propshaft
>
>OK, got me on terms, I should have said that there is pressure on the dog
>gear because the engine is turning the prop against the resistance of the
>water. So to be VERY specific, at idle speed there is resistance from the
>prop and it WANTS to turn slower but cant because it's in gear. Because of
>this the dog gear can not disengage so as you shift from either reverse or
>forward into neutral the kill switch momentarilly kills the ignition so that
>the engine is NOT putting drive pressure thru the gears on the prop and the
>drive gear disengages.
>
>. A momentary spark interruption does not
>> stop the engine. If you try to do full throttle direction changes, the
>> interrupter should move to prevent damage, but in normal operation, the
>> throttle hits the stop before the shift action proceeds, and the
>> decelleration of the motor unloads the clutch dogs, and if the boat is
>> moving, the flow of water over the prop actually aids in unloading
>> it....
>
>Correct;
>This kill switch is not necessarry if you are throttleing back from a plane
>and shift into neutral. The prop is trying to turn faster than the engine
>because the boat is coming down from speed and the water is turning the prop
>faster than the engine. It's also not necessary if your prop is out of the
>water because there is no load on the prop/dog gear
>
>Bottom line, the two causes of interrupter activation is
>> attempting high load shifts, either from too rapid shifting at high rpm
>> or misadjusted cables, or a simulated shift load caused by resistance
>> from a damaged cable or possibly a heavily worn selector shaft bushing
>> and seal.
>
>Correct
>>
>> scottfyi@xxxxxxxxx wrote:
>> When the boat is in the water and I
>>> switch the gear shift to neutral, it will NOT go into neutral most of
>>> the time...it just stays at the "no wake" speed but the shifter is in
>>> neutral. I have to shift it back and forth to get it to finally go to
>>> neutral. Any help would be greatly appreciated.
>>
>> The fact that the control handle is in the neutral position but the
>> clutch is still engaged, is a pretty clear indication that there is not
>> enough throw on the lower cable. This is often caused by the cable end
>> on the interrupter bracket being positioned incorrectly in the slot on
>> the cantilever.. On the v8's and v6's it should be at the bottom of the
>> slot, but if memory serves me correctly, the 4 cyl. plate is inverted
>> and the cable should be at the top of the slot. That will increase
>> throw on the lower cable, and minimize or eliminate any unnecessary
>> movement of the switch.
>
>If it was a bad cable, or high rpms, it would stall the motor while hunting
>back and forth to find neutral.
>
>I did have a bad shift cable that didn't cause symptoms like you'd expect,
>I had a shift cable problem where the kill switch was not being engaged and
>the outdrive would have problems going into and out of gear. This happened
>only in the morning and by warming up the engine (shift cable) the problem
>went away. Replacing the shift cable fixed this problem
>
>I also had a bad cable that manifested symptoms that were slightly unusual,
>the engine would stall when docking, upon further testing it was extreme
>outdrive angles while shifting that caused the stalling (the only time I
>used extreme angles (steering) while shifting was when I was docking the
>boat). Bending the shift cables by having the outdrive at extreme angles
>caused them to bind internally and hang causing the kill switch to stall the
>engine. Replacing the shift cable fixed this problem.
>
>
>> trainfan1 wrote:
>>
>>> Yes, it should... not entirely, just enough to shake the clutch dog off
>>> the gear
>>
>> No, it shouldn't, unless something is wrong...or you're shifting
>> improperly, such as lock to lock..
>>
>>> Different adjustment.
>>
>> Of course it is, it's the throttle cable, but that can cause premature
>> opening of the throttle plate, which in turn causes rpms to increase
>> prior to gear engagement,which causes increased effort tho engage the
>> clutch dogs,which should cause the interrupter. to actuate, which
>> causes the boat to stall, etc etc,...But that's what's supposed to
>> happen if the throttle opens too soon....
>>
>> Jeff Rigby wrote:
>>> Probably the shifter cable is bad, your shifter kill switch is not
>>> engaging.
>>
>> That is when it would engage, if the cable was bad
>>
>>
>> JIMinFL wrote:
>>> The shift bellow doesn't seal water out of the cable. If the bellow leaks
>>> the boat will take on water. A defective shift shaft bushing is the main
>>> cause for water intrusion into the shift cable
>>
>> You're absolutely right,,,
>>
>

--
John H

******Have a spectacular day!******
.

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