I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I've had false high RPM indications that were the result of a loose ground
wire. Check the wires at the connections to the indicator first - it's
probably easier to get to.

"Don" wrote in message
om...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

(Don) wrote in message . com...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I would guess that it is the actual tach that is bad, seeing how you
are reading SOMETHING. I'd think if the wiring were bad, you would
read zero R.P.M.'s.

In article , (basskisser) wrote:

(Don) wrote in message
. com...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I would guess that it is the actual tach that is bad, seeing how you
are reading SOMETHING. I'd think if the wiring were bad, you would
read zero R.P.M.'s.

Ever hear of excessive resistance? One can have "bad" wiring and
still get a reading...(albeit usually much lower).

(Henry Blackmoore) wrote in message hlink.net...
In article , (basskisser) wrote:

(Don) wrote in message
. com...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I would guess that it is the actual tach that is bad, seeing how you
are reading SOMETHING. I'd think if the wiring were bad, you would
read zero R.P.M.'s.

Ever hear of excessive resistance? One can have "bad" wiring and
still get a reading...(albeit usually much lower).

Ever hear of reading the post before knee-jerking a reaction? It reads higher.

In article , (basskisser) wrote:

(Henry Blackmoore) wrote in message
hlink.net...
In article ,
(basskisser) wrote:

(Don) wrote in message
. com...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I would guess that it is the actual tach that is bad, seeing how you
are reading SOMETHING. I'd think if the wiring were bad, you would
read zero R.P.M.'s.

Ever hear of excessive resistance? One can have "bad" wiring and
still get a reading...(albeit usually much lower).

Ever hear of reading the post before knee-jerking a reaction? It reads higher.

Well no sh*t Sherlock. Which is precisely why I posted that sentence in
parenthesis. However according to your ignorant statement above a tach
would never read anything if the wiring were "bad". I was responding to
YOUR (drug-influenced?) comment and NOT the whole post.

Sheesh. You really ought to clear your mind for awhile and leave that
weed alone.

(Henry Blackmoore) wrote in message nk.net...
In article , (basskisser) wrote:

(Henry Blackmoore) wrote in message
hlink.net...
In article ,
(basskisser) wrote:

(Don) wrote in message
. com...
I had a problem late last year with the RPM's on my boat. Well, it
was not really the RPM's, just the reading on my tach.

Sometimes when first starting out for the day the tach would show 5500
to 6000 RPM's even though I know they were not that high. My boat
max's out at about 4600. I have a 26 foot Weekender with the 350/260
combination. I know by the sound of the motor too. Then after some
amount of minutes the tach reading drops back to what it should be,
around 3500, with no change in the sound of the motor.

So I have a bad tach. My question is is it usually the actual guage
that goes bad or is it the cable or whatever the cable attaches to on
the motor/outdrive side to pick up the RPM's. I guess I don't really
know where the cable attaches to read the RPM's.

many thanks

I would guess that it is the actual tach that is bad, seeing how you
are reading SOMETHING. I'd think if the wiring were bad, you would
read zero R.P.M.'s.

Ever hear of excessive resistance? One can have "bad" wiring and
still get a reading...(albeit usually much lower).

Ever hear of reading the post before knee-jerking a reaction? It reads higher.

Well no sh*t Sherlock. Which is precisely why I posted that sentence in
parenthesis. However according to your ignorant statement above a tach
would never read anything if the wiring were "bad". I was responding to
YOUR (drug-influenced?) comment and NOT the whole post.

Sheesh. You really ought to clear your mind for awhile and leave that
weed alone.

Then why to hell did you POST it??? Drunk again?

I assume you are running a carburated Mercruiser with their Thunderbolt
solid state ignition. I had a similar problem with one of the 4.3L V6
motors in my 'Dancer. I found a clogged vent had caused some corrosion on
the trigger rotor inside the distributor that was intermittently causing
extra pulses, causing high readings on the tachometer. I cleaned up the
interior of the distributor and polished the rotor. That took care of my
tach problem and also smoothed out the idle on that motor.

Hope this helps. Good luck.