On Jul 8, 12:11 pm, "Jim" wrote:
"Tim" wrote in message

ups.com...
| On Jul 8, 11:52 am, Tim wrote:
| On Jul 7, 12:02 pm, wrote:
|
|
|
| A buddy of mine has a Crownline 20 foot bowrider, with quicksilver
| commander 3000 controls, a 350 MPI engine... at times, the engine
| won't fire or crank no click or nothing, however all electronics on
| board work properly. I.E. Bildge, blower, hatch, trim lights stereo
| so on so fourth, and when you take the power control lever, and run
| it full forward and full reverse then return it to neutral while the
| key is off, the engine will fire up right away.... I'm tempted to
| tell him to check the wires to the ignition switch from the neutral
| lock out switch, or the switch itself.. anyone have similar
| troubles?... how did it get resolved?..
|
| Thanks.- Hide quoted text -
|
| - Show quoted text -
|
| Hmm, I don't kwow how that happened. I hit reply and it made a blank
| post!
|
| Anyhow, I thinkt he problem is in the momentary kill switch.
| Mercruiser has a "kill" switch built into the mechanism, that will all
| the engin to be momtarily shut off while shifting to forward or
| reverse, to allow the gears to mech properly without any engine load.
| I feel it's not defective, but needs adjustment, but if it's
| defective, it's holding "open" untill the shift mechanism jars it
| loose.
|
| just an opinion.
|
|
That's a popular opinion but couldn't be further from the truth. The shift
interrupter will only cause the engine to stumble when pulling OUT of gear.
99.9% of the time that it closes and kills the ignition is because of a
problem with the lower cable or linkage.



I stand corrected.

Pulled this from another board:

"The switch in question is common to many engines. What it does is to
momentarily kill the engine, only for a few milliseconds, as the
clutch dog or cone disengages. For a brief moment while the clutch
mechanism is moving, its teeth or surfaces are only just on the verge
of being engaged, and if a power pulse from the engine coincides with
this instant, a bit of metal can be scraped off of the clutch
mechanism. So by killing the engine for a few milliseconds as the
clutch moves, we can guarantee that no power pulse will coincide with
that instant where the mechanism is most vulnerable. Once the clutch
has moved, the spark plugs get their power back and the engine keeps
on turning. (All of this should happen in less than a couple of
revolutions, usually, and so the engine doesn't actually stop
turning.)
What we have here appears to be that the momentary-kill switch is
jammed, and so does not return to its normal position quickly enough
after the shift. I would suggest thoroughly inspecting all throttle/
shift connections and cables, then replacing the switch...."