fuel gauge voltage regulator

[Mainer311]

Wow, that's pretty slick, and very cheap.

Based on the reviews about a 10% failure rate.

What do you expect for $7.70?

[Curtis]

Wow, that's pretty slick, and very cheap.

Based on the reviews about a 10% failure rate.

What do you expect for $7.70?

Not much, but I'll bet the failure rate is even higher and people haven't gone back to comment. Looks to me like you'll still have to put it in something since it is just a board.

[andyroo]

Scroll up, I have one.

I think it works...I was having problems with my sending unit when I put it on and now my fuel tank is off the car so I can't 100% confirm. The temp gauge seemed to work so that's good.

But I tested the regulator with my voltmeter and it was spot on. No reason it shouldn't work. I may 3d print a case for it once I dial it in.

- Andrew

[Mainer311]

Digikey has nice little injection molded ABS project boxes for cheap, but 3D printing your own is cooler.

[Nissanman]

Well, everybody else is doing it so I thought I would get into the act too

I purchased a 3 terminal Voltage Regulator which outputs -8 Volts, suitable for the gauges.
Pins from the LHS are Ground, Input[-ve 12V] and Output[-ve 8V]

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It is placed in series with the 12V supply to the Fuel Gauge.

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The device is mounted on to a tiny piece of veroboard and housed in a gutted fluro tube starter

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Nice steady output voltage.

I haven't noticed a change from a series resistor to the VR since the Fuel Gauge is at mid scale atm.
Hopefully though, the E and F readings will be more accurate again than with the resistor.

For the POSITIVE GROUND cars the device is an LM7908, -8V output.
The equivalent for NEGATIVE GROUND cars is LM7808, +8V output.

All of a $1.45 at my local Electronics Store

[RBMann]

Scroll up, I have one.

I think it works...I was having problems with my sending unit when I put it on and now my fuel tank is off the car so I can't 100% confirm. The temp gauge seemed to work so that's good.

But I tested the regulator with my voltmeter and it was spot on. No reason it shouldn't work. I may 3d print a case for it once I dial it in.

- Andrew

How did you wire it into the system? Input + from battery, output + to gauges and both negatives to ground?

[andyroo]

That sounds about right...I'll let you know this weekend though.

I do still need to bench test my sending unit and fuel gauge.

- Andrew

[RBMann]

Okay, thanks.

[beautyandplay]

Can someone tell me the correct in and out voltage for the in-line resistor mounted on the steering column of a 1966 model? My in is 14 v. and the out is 4 v. which is probably contributing to my incorrect fuel, temp and oil pressure readings. Thanks! Tom

[notoptoy]

I believe you should have 12-14 in and 8V out.

[beautyandplay]

I believe you should have 12-14 in and 8V out.

Many thanks! Tom