M5 with 12 volt sending unit.

[pszikszai]

I am converting my M5 to 12 Volt.
I read previous discussions on this subject, none seem to address my question.

The only question I have is where to reduce the voltage for the gas gage --
Everything is 12 volts.
The sending unit is 12 volts.
The gas gage is 6 volts.
I was planning to run 12 volts to the gas gage's battery terminal
and reduce the voltage from the tank or sending unit?
Do I have it right or backwards?
Thanks
Paul

[Dick Steinkamp]

I'd run a 6V sending unit and a 6V gauge and reduce the voltage to both...

http://wire-works.com/showpage.php?page=detail.htm&partid=151

[pszikszai]

As always I appreciate your sugestions.
However I already installed a 12Volt sending unit and do not wish to remove it unless the situation is unworkable.
Paul

[41 Frank]

As Dick indicated what you are trying to do will not work as you need to use a 6v sender with a 6v gauge and than use a Runz voltage reducer at the gauge. You cannot reduce the voltage to the 12 volt sender as it operates by sensing voltage. When you reduce that voltage from what it was intended for the gauge will be horribly inaccurate. I've done what you are trying to do and it only works if you do it as described. If you can't change back to a 6v sender the only option is to use a gauge made for 12volts that is compatible with your sender.

[gordr]

Frank and Dick have it nailed. The sending unit and the gage unit are electrically matched to each other. Trying to use a 12 volt sending unit with a 6 volt gage is like trying to force a coarse thread nut onto a fine thread stud. You run a risk of damaging both the gage AND the sending unit.

You might find that the "guts" of a 12 volt Stewart-Warner gage can be installed in the M5 cluster. You might be able to rob suitable guts from a Lark cluster. If you can make it fit, that would be the most elegant solution.

Mixing and matching gages from different makers is at least as "iffy" as mixing and matching voltages, BTW.

Gord Richmond, within Weasel range of the Alberta Badlands

[pszikszai]

Thank you all for the suggestions.
I took your advices and installed a 12 volt gage.
Painted it almond.
Looks fine.
Paul