Fuel flow sensor needed.

[moparguy]

I've built and installed a 15gal. fuel tank between the passanger side frame rail and bed panel. To transfer fuel to the main tank, I've installed a little 12v pump and filter that pumps a gal. every 2 minutes or so, my concern is that without a way to be sure I'm pumping fuel, the aux. pump won't last very long when I've emptied the tank and run it a few too many minutes.



One solution I've considered is installing a mechanical fuel gauge, but this clutters the cab even more.



What I'd like to find is a simple inline device that could cause a light to come on it the cab either when fuel was flowing or not flowing.



Cheap and simple is good. Any ideas?



Thanks, RJR

 

[moparguy]

OK guys, I'm bumping this back to the top. One thought I've had is something like a oil pressure sending unit that when T'ed into the fuel line from the aux tank would cause a light to come on or go off when the tank is empty and fuel pressure drops.



Any ideas about the feasibality of this idea, comments on type sending unit that might work.



Thanks, RJR

 

[JimBob24]

I have a very similar set-up as yours and have the same concerns. Since we are pumping into an open tank without any restrictions I doubt that there would be enough fuel pressure to activate a pressure sending unit. Probably would have to engineer something using a fuel flow type sensor.

 

[DougJones]

Momentary Switch? I think you buy these for any time interval? Also you'd have to estimate the time needed, and surely you'd fall short or long on emptying the tank, but would close be good enough?

 

[cap-n-cray]

A fuel flow sensor would be a great accessory. I think fuel flow would be a better way of monitoring the lift pump. It would let you know how much fuel is flowing to the injection pump not just the pressure. Good pressure with very little flow would not be a good thing for a fuel staved injection pump. The problem is flow meters are a little expensive. There might be one that just shows if there is flow for a transfer pump. Maybe a on/off fuel level sensor would work best and least expensive. Another thought is to restrict the output slightly and use a pressure switch that would be off with no pressure. Someone must have something for this purpose for planes or boats.



McMaster-Carr has them. Do a search on flowmeter. They a pricey. :{



An additonal idea is a amp meter that would show the pump's power usage. Less amps when the pump is running with no work more when it is pumping. A light in parallel it would be brighter when the pump is not pumping anything.



Cary