Has anyone run 2 fuel gauges in gauge cluster

I put two 19-gallon poly marine (boating) fuel tanks in my M715. I added an electrically operated tank switch and a DPDT (I think) toggle switch so when I switch between tanks I also switch the sender feeds to the gauge. As long as your senders match the gauge this will work very well. NAPA has the electric switch valves and the toggle switches (although a regular electronics place will have the same type of toggle switch a little cheaper).

That said, if you have a redundant gauge in there anyway I'd be more inclined to just go with the 2nd gas gauge. Be simpler to do.

Stan

 

i cant seem to think of there being any problem. you woyuuld just have to wore it the same as before. it would get constant power so both your guages would work at the same time. i actually like that idea, i went with a second fuel gauge on my dash and still have the unused temp in the cluster. cool idear!!!

 

That is a very ingenious idea. Left one for under the seat and right one for the rear?

 

I run a dual tank setup in my 71. Used a 6 inlet pet**** from an early 70's Ford p'up to handle the fluids. Simply used a three way switch on the dash to switch sending units. Both senders worked fine with this configuration.

 

Why would this be a problem, I have the same gauge you do with my factory rear tank.

 

I installed a second tank and ran both sender units through one gauge using a triposition switch. I do have a problem with the sending units not matching the gauge. The front tank works fine...but the rear shows half full when empty and pegged when full. Anyone have any clues on how to correct this? Sorry I'm not trying to steal this thread.

 

You can correct this to a small degree using a resistor inline to the sender. I have an original gauge but needed to install a new sender and float assembly. The newer sender was a Jeep style unit and was very close to being correct but I had to add a resistor to correct for a slight mismatch. My gauge would peg at full and never show completely empty. If you had the opposite problem (gauge never shows full) the resistor trick does not work for that problem.

Start by taking the sender wire off the sender and putting a variable resistor (from any r shack) between the sender wire and the sender (aligator test leads work well for this, I keep a dozen of them on hand for this kind of thing). I had a full tank at the time so I adjusted the variable resistor so the gauge did not peg any more. Then I pulled the sender from the tank and let it fall to the "empty" position and made sure the gauge would still read correctly. Once I had that, I pulled the variable resistor, read it with a meter and then found a regular resistor of that value and soldered it inline in the sender wire.

Note that this will only work for a very slight mismatch between sender and gauge. Whenever possible match the sender to the gauge. Trying to match a new sender to an old gauge can be tricky. Not only does the ohm range have to match, but the gauge's full/empty to sender's hi/low ohms relationship has to match as well. If the gauge is "looking" for 10 ohms empty, but your sender reads 10 ohms full, it won't work.

Original Jeep gauge wants to see 73 ohms empty, 10 full. The general standard for aftermarket "universal" gauges for auto and marine (boating) is 240 ohms empty, 33 ohms full. You can get a "universal" 240-33 sender kit from NAPA that can be adjusted to fit most tanks, but you'll have to use the gauge in the kit (or any other 240-33 gauge) to make it work. And regardless of what sender/gauge combo you want to use, you must give the gauge and sender good grounds!

Stan

 

Great info and thankyou! I will give it a try and let you know how it works. I will be posting a few pics of my rig soon. Back to the original thread.. I think it would be useful to have two fuel gauges so you know how much fuel you have all the time.