"Ed Barchetta" wrote in message


The wire goes from the coil, through the
throttle/shifter and then to the tach.

Is there a safety cutoff switch lanyard on the throttle/shifter assembly?
If so, then my guess is that you have some water in the cutoff switch.

There are also some shift assemblies that have a momentary "engine kill" as
it shifts, I assume so that the actual shift occurs at the lowest possible
engine RPM. If this mechanism is in the shifter assembly, then I would
suspect that either water got into that or the switch is failing.

If it is a safety lanyard issue, I would be tempted to just bypass it. If
it is a shifting function, then I would tear apart the shifter and dry out
or replace whatever is in there that the wire touches.

Rod

On Tue, 17 Feb 2004 18:17:08 GMT, "Ed Barchetta"
wrote:

"Short Wave Sportfishing" wrote in message
.. .

Here's a couple of suggestions, although these might not be the
answer.

Check the wire along it's route for abrasion, cracked insulation, etc.
You might also want your mechanic to test the coil. Pull the tach and
try it on another engine. I would suspect either the tach itself or a
short somewhere along the wiring route.

I've already eliminated the coil from the equation so it's between the coil
and the throttle. The visible wiring looks good with no cracks. I'll have to
get into the throttle area to examine the connections/wire.

I'm not familiar with the throttle system you use, but I have worked
on a similar age Merc throttle control and I believe the tach wire,
along with temp sensor, oil pressure etc., went to a connector block
and then to the instruments. Pull the connector apart and check for
corrosion, shorts, etc.

I can't remember what my guy called it but the 'switch' inside the throttle
area that stops you from being able to go into gear while the rpm's are too
high may be related. By disconnecting that system at the coil, we run ok,
although after any length of high speed run (25 mph and 3500 rpm), I have to
slow to trolling speed for about a minute before I can get it back into
neutral or manuever into a dock.

Neutral safety switch - somebody mentioned that and it certainly could
be the answer. And, as it happens, I can answer that.

It's not hard to get to - you have to remove the control from where it
is mounted to get behind it, then, and this may vary a little, remove
the rear/front cover - it may be a reed switch or contact switch -
again, I'm not sure of what kind of switch. It will be on or near a
cam located on the throttle arm pivot point. It could be inboard in
the throttle control body - the one I worked on was located there, but
I replaced the control with one that was on the outside.

I'm guessing here, but you may not be able to get a new switch. I
have worked on one of these for somebody in the family who had a merc
controller of the same vintage and while I could modify one to work,
it wasn't very good repair. You may have to consider a new control.
Hopefully not.

Out of curiosity, do you have to search for neutral when shifting in
and out of gear? If so, it may be more than just the switch in the
throttle.

Good luck.

Later,

Tom
S. Woodstock, CT
----------

"Fisherman are born honest, but they get
over it." - Ed Zern

Pull the wire from tach and engine and check with an Ohm meter for partial
shorts. Should be infinite resistance.
Bill

"Ed Barchetta" wrote in message
om...
This problem popped up after a trip to the mechanic and he suggested
that it might take some time $$ to diagnose. Hopefully someone has
seen this before. I've got a 1982 Mercruiser 140 (181) that developed
a rough disposition after a few minutes on the water recently. It
started 'coughing' at planing speed and then idled bad to the point of
stalling, even back on the trailer. While the engine would be
sputtering, the tach would show the opposite of what was going on, ie:
when the engine would nearly stall the tach would jump up erratically
and alternately nearly bottom out when the rpm's rose. I found that if
I disconnected the tach connection on the coil, the engine idled and
cruised normally. The wire goes from the coil, through the
throttle/shifter and then to the tach. To eliminate (or verify) that
the tach itself might be the problem, I disconnected it at it's end
and reconnected the coil end. The rough engine returned immediately.
Without tearing out the wiring, I'm guessing a short or disconnection
in the throttle area but don't really know what to expect once I'm in
there. Has anybody any suggestions or experience with such a problem?

Thanks,
Ed

"Short Wave Sportfishing" wrote in message
...

Neutral safety switch - somebody mentioned that and it certainly could
be the answer. And, as it happens, I can answer that.

It's not hard to get to - you have to remove the control from where it
is mounted to get behind it, then, and this may vary a little, remove
the rear/front cover - it may be a reed switch or contact switch -
again, I'm not sure of what kind of switch. It will be on or near a
cam located on the throttle arm pivot point. It could be inboard in
the throttle control body - the one I worked on was located there, but
I replaced the control with one that was on the outside.

I'm guessing here, but you may not be able to get a new switch. I
have worked on one of these for somebody in the family who had a merc
controller of the same vintage and while I could modify one to work,
it wasn't very good repair. You may have to consider a new control.
Hopefully not.

Out of curiosity, do you have to search for neutral when shifting in
and out of gear? If so, it may be more than just the switch in the
throttle.

Thanks for the info Tom. That should help me a great deal. To answer your
question, no, I don't have to look for neutral. It's got pretty solid F-N-R
positions. It's just gets all 'wound up' on the engine side after a moderate
to high rpm run and takes a little slow idling to get it 'unwound' or
loosened up enough to slide out of gear. Of course, when I hook the tach
wire back up at the coil side, the shifting is smooth but the engine
sputters.

Ed

From my limited electrical knowledge, wouldn't the switch in the throttle
provide an out for the Ohm meter's current? Ed

"Calif Bill" wrote in message
ink.net...
Pull the wire from tach and engine and check with an Ohm meter for partial
shorts. Should be infinite resistance.
Bill

"Ed Barchetta" wrote in message
om...
This problem popped up after a trip to the mechanic and he suggested
that it might take some time $$ to diagnose. Hopefully someone has
seen this before. I've got a 1982 Mercruiser 140 (181) that developed
a rough disposition after a few minutes on the water recently. It
started 'coughing' at planing speed and then idled bad to the point of
stalling, even back on the trailer. While the engine would be
sputtering, the tach would show the opposite of what was going on, ie:
when the engine would nearly stall the tach would jump up erratically
and alternately nearly bottom out when the rpm's rose. I found that if
I disconnected the tach connection on the coil, the engine idled and
cruised normally. The wire goes from the coil, through the
throttle/shifter and then to the tach. To eliminate (or verify) that
the tach itself might be the problem, I disconnected it at it's end
and reconnected the coil end. The rough engine returned immediately.
Without tearing out the wiring, I'm guessing a short or disconnection
in the throttle area but don't really know what to expect once I'm in
there. Has anybody any suggestions or experience with such a problem?

Thanks,
Ed

On Wed, 18 Feb 2004 14:55:45 GMT, "Ed Barchetta"
wrote:


"Short Wave Sportfishing" wrote in message
.. .

Neutral safety switch - somebody mentioned that and it certainly could
be the answer. And, as it happens, I can answer that.

It's not hard to get to - you have to remove the control from where it
is mounted to get behind it, then, and this may vary a little, remove
the rear/front cover - it may be a reed switch or contact switch -
again, I'm not sure of what kind of switch. It will be on or near a
cam located on the throttle arm pivot point. It could be inboard in
the throttle control body - the one I worked on was located there, but
I replaced the control with one that was on the outside.

I'm guessing here, but you may not be able to get a new switch. I
have worked on one of these for somebody in the family who had a merc
controller of the same vintage and while I could modify one to work,
it wasn't very good repair. You may have to consider a new control.
Hopefully not.

Out of curiosity, do you have to search for neutral when shifting in
and out of gear? If so, it may be more than just the switch in the
throttle.

Thanks for the info Tom. That should help me a great deal. To answer your
question, no, I don't have to look for neutral. It's got pretty solid F-N-R
positions. It's just gets all 'wound up' on the engine side after a moderate
to high rpm run and takes a little slow idling to get it 'unwound' or
loosened up enough to slide out of gear. Of course, when I hook the tach
wire back up at the coil side, the shifting is smooth but the engine
sputters.

I would suspect the neutral switch or wiring then.

It could, possibly, be the tach it'self. While I didn't have a
problem like yours, the FICHT on my Ranger had a shifting problem
related to the tach and/or tach control on the engine

Later,

Tom
S. Woodstock, CT
----------

"Fisherman are born honest, but they get
over it." - Ed Zern

Hey, you've got some places to start with the troubleshooting.

Good luck.

The tach wire should only go through a connector block. There is no reason
for a switch in that line. The Neutral Switch is only to allow the
starter's solenoid wire to be open when not in neutral.
Bill

"Ed Barchetta" wrote in message
...
From my limited electrical knowledge, wouldn't the switch in the throttle
provide an out for the Ohm meter's current? Ed

"Calif Bill" wrote in message
ink.net...
Pull the wire from tach and engine and check with an Ohm meter for
partial
shorts. Should be infinite resistance.
Bill

"Ed Barchetta" wrote in message
om...
This problem popped up after a trip to the mechanic and he suggested
that it might take some time $$ to diagnose. Hopefully someone has
seen this before. I've got a 1982 Mercruiser 140 (181) that developed
a rough disposition after a few minutes on the water recently. It
started 'coughing' at planing speed and then idled bad to the point of
stalling, even back on the trailer. While the engine would be
sputtering, the tach would show the opposite of what was going on, ie:
when the engine would nearly stall the tach would jump up erratically
and alternately nearly bottom out when the rpm's rose. I found that if
I disconnected the tach connection on the coil, the engine idled and
cruised normally. The wire goes from the coil, through the
throttle/shifter and then to the tach. To eliminate (or verify) that
the tach itself might be the problem, I disconnected it at it's end
and reconnected the coil end. The rough engine returned immediately.
Without tearing out the wiring, I'm guessing a short or disconnection
in the throttle area but don't really know what to expect once I'm in
there. Has anybody any suggestions or experience with such a problem?

Thanks,
Ed

"Ed Barchetta" wrote in message ...
"David Ward" wrote in message
ink.net...
snip
You already isolated the problem to the wiring - so the next step would be
to inspect the loom and see if there's an abrasion problem and how many
other wires will be affected sooner or later - then go enjoy the water.

Dave

Sorry for my ignorance, but what's the 'loom'?

Ed

It's where Inspector Clouseau spends ze night at ze hotel.

Or, it's the bundle of wires going from yout control bokes and gages to your engine.

%mod%

"Ed Barchetta" wrote in message ...
"Kenneth670" wrote in message
...
You might want to chech the shift interupter switch to see if it might be
defective or stuck if your setup has one.

I wonder if that's the part that my mechanic was referring to. Is this what
prevents you from going into gear with the rpm's too high and located in the
throttle area? If so, that should be easily replaceable and not too
expensive, eh?

Ed

The shift interrupter switch cuts the ignition briefly when shifting
into gear to lessen the slamming when the shift dog engages. It
doesn't actually physically prevent the shift lever from being put
into gear at high RPM.

If the interrupter is acting up, it could concievably send spikes down
the tach wire and confuse the tach.

%mod%

"
Sorry for my ignorance, but what's the 'loom'?
Is a loom one cable that hold different wires. I thought it was a loon, but we call it a snake sometimes also.