Bruce wrote:

As far as the instrument problem is concerned the logical plan would
be to undo the last thing done, i.e., disconnect the Tach and see what
happens?

Hardly rocket science but if only one thing changes - the bloke
connects a different tachometer - and all the instruments fail then

Which I will of course try today. Yesterday I tried switching the old tach
wires (see original post). That was a "no go" because the connectors allow
only one proper connection on the new instrument. Note that only the temp
gauge is acting up. All other gauges (oil, voltage, tach, alarms, lights,
etc.) perform properly.

--
Good luck and good sailing.
s/v Kerry Deare of Barnegat
http://home.comcast.net/~kerrydeare

On Thu, 8 Apr 2010 06:46:02 -0400, "Armond Perretta"
wrote:

Bruce wrote:

As far as the instrument problem is concerned the logical plan would
be to undo the last thing done, i.e., disconnect the Tach and see what
happens?

Hardly rocket science but if only one thing changes - the bloke
connects a different tachometer - and all the instruments fail then

Which I will of course try today. Yesterday I tried switching the old tach
wires (see original post). That was a "no go" because the connectors allow
only one proper connection on the new instrument. Note that only the temp
gauge is acting up. All other gauges (oil, voltage, tach, alarms, lights,
etc.) perform properly.

Still, I'd reverse my "repair" and see what happens. A heat gage going
full scale indicates that somewhere between the instrument the temp.
sender you have a short to ground and/or the sender in shorted to
ground.

You can isolate things a bit more by disconnecting the existing
connections to the Temp. Gage and connecting a jumper from some known
source of power to the proper terminal on the gage, then temporarily
connect the wire from the temp sender, to the gage and see how it
works.Try using a jumper of some sort, make a whole new connection
from the gage to the sender and see what happens. This should give you
a pretty good indication of what is working and what is not. If you
find that isolated from everything else on the panel the Temp Gage
works then you can investigate the "everything else".

And yes, this is exactly, leaving out experience, how a professional
instrumentation guy will do it - isolate the instrument and it's
sender from everything else to determine whether it is the instruments
themselves or "everything else", fix either the instrument or
"everything else".


Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

Bruce wrote:

... I'd reverse my "repair" and see what happens. A heat gage going
full scale indicates that somewhere between the instrument the temp.
sender you have a short to ground and/or the sender in shorted to
ground.
...
... this is exactly, leaving out experience, how a professional
instrumentation guy will do it - isolate the instrument and it's
sender from everything else to determine whether it is the instruments
themselves or "everything else", fix either the instrument or
"everything else".

Thanks, Bruce. I think I am getting close to a solution for this issues
thanks to many comments here, on the Volvo forums, and elsewhere. I am
betting that I simply removed the wires from the temp sender when trying to
remove the wires from the tach sender. My manuals and Volvo downloads give
essentially no exact guidance, pictures, or diagrams on which sensor is
which, and on top of that there is really no room in the engine compartment
to look around and see the entire layout. This of course has been a problem
from day one with small sailing boats.

I just sent the following to the Volvo forum. Additional comments are of
course welcome. BTW thanks to you all who are providing serious and
detailed suggestions. I readily admit I am an amateur when it comes to
marine diesels, despite having messed with them 30 or so years. Apparently
some few readers believe it's necessary to remind me of my ignorance in
these matters. Rest assured, friends and others, I am well aware of my
limitations and have been humbled by the sea many times.

Set to Volvo forums:

"I think we're getting warm. Yesterday I tried various combinations,
including just disconnecting the wire to the "w" lug. I had assumed that
this wire, one of 2, belonged to the old tach. When I then tried the engine
with this wire disconnected the tach still worked but the temp gauge was
"dead."

"In other words I suspect that my problem is that instead of disconnecting
the wires I may have mistakenly assumed belonged to the old tach, I actually
disconnected the wires from the temp sender, and then connected one of these
to "w" on the alternator. This fits all the symptoms so far, and could
easily have happened since I am not really sure which sender is temp and
which is revs. My manual does not show the locations clearly. Another clue
is that the pair I disconnected has 2 different sized lugs, fitting the
description of the temp sender wires given to me by Richard Vosbury of
Annapolis. I suspect the larger lug is the actual temp resistor and the
smaller lug is the temp alarm.

Today I will run down to the boatyard and try again, this time using the
correct pair of wires (assuming I can locate them somewhere in the vicinity
of the alternator on the starboard side of the engine). In he meantime, any
more comments on these suppositions? Putting all the comments together so
far is at least giving this confused amateur some ideas on how to proceed.
Thanks, gentlemen."

--
Good luck and good sailing.
s/v Kerry Deare of Barnegat
http://home.comcast.net/~kerrydeare

On Fri, 9 Apr 2010 04:14:55 -0400, "Armond Perretta"
wrote:

Bruce wrote:

... I'd reverse my "repair" and see what happens. A heat gage going
full scale indicates that somewhere between the instrument the temp.
sender you have a short to ground and/or the sender in shorted to
ground.
...
... this is exactly, leaving out experience, how a professional
instrumentation guy will do it - isolate the instrument and it's
sender from everything else to determine whether it is the instruments
themselves or "everything else", fix either the instrument or
"everything else".

Thanks, Bruce. I think I am getting close to a solution for this issues
thanks to many comments here, on the Volvo forums, and elsewhere. I am
betting that I simply removed the wires from the temp sender when trying to
remove the wires from the tach sender. My manuals and Volvo downloads give
essentially no exact guidance, pictures, or diagrams on which sensor is
which, and on top of that there is really no room in the engine compartment
to look around and see the entire layout. This of course has been a problem
from day one with small sailing boats.

I just sent the following to the Volvo forum. Additional comments are of
course welcome. BTW thanks to you all who are providing serious and
detailed suggestions. I readily admit I am an amateur when it comes to
marine diesels, despite having messed with them 30 or so years. Apparently
some few readers believe it's necessary to remind me of my ignorance in
these matters. Rest assured, friends and others, I am well aware of my
limitations and have been humbled by the sea many times.

Set to Volvo forums:

"I think we're getting warm. Yesterday I tried various combinations,
including just disconnecting the wire to the "w" lug. I had assumed that
this wire, one of 2, belonged to the old tach. When I then tried the engine
with this wire disconnected the tach still worked but the temp gauge was
"dead."

"In other words I suspect that my problem is that instead of disconnecting
the wires I may have mistakenly assumed belonged to the old tach, I actually
disconnected the wires from the temp sender, and then connected one of these
to "w" on the alternator. This fits all the symptoms so far, and could
easily have happened since I am not really sure which sender is temp and
which is revs. My manual does not show the locations clearly. Another clue
is that the pair I disconnected has 2 different sized lugs, fitting the
description of the temp sender wires given to me by Richard Vosbury of
Annapolis. I suspect the larger lug is the actual temp resistor and the
smaller lug is the temp alarm.

Today I will run down to the boatyard and try again, this time using the
correct pair of wires (assuming I can locate them somewhere in the vicinity
of the alternator on the starboard side of the engine). In he meantime, any
more comments on these suppositions? Putting all the comments together so
far is at least giving this confused amateur some ideas on how to proceed.
Thanks, gentlemen."


Just out of curiosity what are the connections to your tach marked?
You mention "W", but the others?

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

Armond Perretta wrote:
... I think I am getting close to a solution for this issues thanks to
many comments here ... I am betting that I simply removed the wires from
the temp sender when trying to remove the wires from the tach sender ...

The subject line says it all. DO NOT RTFM! Had I ignored the instructions
packaged with the new tach and just switched it out, everything would have
been OK from the beginning. The instructions evidently do not take into
account that during the manufacturing run of this model quite a few changes
were incorporated, including the latest wiring for the tach. Unfortunately
no one in the marketing department was notified that changes in the
brochures were in order. Today I just undid all the changes made according
to the installation literature, essentially just dropped in the replacement
tach, and all works per design.

--
Good luck and good sailing.
s/v Kerry Deare of Barnegat
http://home.comcast.net/~kerrydeare

On Fri, 9 Apr 2010 14:02:18 -0400, "Armond Perretta"
wrote:

Armond Perretta wrote:
... I think I am getting close to a solution for this issues thanks to
many comments here ... I am betting that I simply removed the wires from
the temp sender when trying to remove the wires from the tach sender ...

The subject line says it all. DO NOT RTFM! Had I ignored the instructions
packaged with the new tach and just switched it out, everything would have
been OK from the beginning. The instructions evidently do not take into
account that during the manufacturing run of this model quite a few changes
were incorporated, including the latest wiring for the tach. Unfortunately
no one in the marketing department was notified that changes in the
brochures were in order. Today I just undid all the changes made according
to the installation literature, essentially just dropped in the replacement
tach, and all works per design.

Congratulations!
Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

On 09/04/2010 19:02, Armond Perretta wrote:
Armond Perretta wrote:
... I think I am getting close to a solution for this issues thanks to
many comments here ... I am betting that I simply removed the wires from
the temp sender when trying to remove the wires from the tach sender ...

The subject line says it all. DO NOT RTFM! Had I ignored the instructions
packaged with the new tach and just switched it out, everything would have
been OK from the beginning. The instructions evidently do not take into
account that during the manufacturing run of this model quite a few changes
were incorporated, including the latest wiring for the tach. Unfortunately
no one in the marketing department was notified that changes in the
brochures were in order. Today I just undid all the changes made according
to the installation literature, essentially just dropped in the replacement
tach, and all works per design.

Excellent!
I may have underestimated the creativity of your wiring.:-)

On Thu, 8 Apr 2010 06:46:02 -0400, "Armond Perretta"
wrote:

Bruce wrote:

As far as the instrument problem is concerned the logical plan would
be to undo the last thing done, i.e., disconnect the Tach and see what
happens?

Hardly rocket science but if only one thing changes - the bloke
connects a different tachometer - and all the instruments fail then

Which I will of course try today. Yesterday I tried switching the old tach
wires (see original post). That was a "no go" because the connectors allow
only one proper connection on the new instrument. Note that only the temp
gauge is acting up. All other gauges (oil, voltage, tach, alarms, lights,
etc.) perform properly.


Leave the tach unconnected and see whether the other instruments work.
then connect the tach and see. should tell you something. The tach has
three wires? Battery, or Ign., Ground, and Signal?

Does it have a multitude of jumpers or micro switches to set RPM and
number of poles on the alternator?
Cheers,

Bruce
(bruceinbangkokatgmaildotcom)