Swam ammeter for fuel gauge

[Oscar]

Going alternator, 42A..... not sure about sending that through my ammeter. (30A)

Anyone want to trade my ammeter for his fuel gauge? I have a dual tank setup, that would work nicely;

[joulandy]

Hi,

I run a 60a/h Bosch and have never seen the ammeter pegged - i have removed the meter a long time ago but would be interested how many amps you show on the meter after conversion

[Oscar]

Yeah, I am getting more and more reports that I can just let it sit. Going to give that a try.

[64Blue]

I have a 64 S2A with an alt conversion. I just completed a new harness install (thanks for the help and patience form the membership on my questions!)

I do have a couple remaining questions regarding the Ammeter, Voltmeter and Fuel gauge.

on the Ammeter, is it possible to have it work correctly WITHOUT wiring it in series with the main supply? I was hoping to figure out a clever way to use it so it's working, but not have to hack up my new harness.

on the Voltmeter, I think I read that one can just add two jumpers from the test plug wiring. One of the hot wires going to one of the spade clips. Where does the ground to to? the chassis?

on the fuel gauge, I just wanted to confirm it operates by a variable resistant of the mechanical gauge in the tank... and so should have supply (green) to the gauge, and the green with black stripe going to the fuel tank.


thanks!

[slowmo]

The ammeter measures the current flowing through it. Connecting it somehow in parallel will not give an accurate indication of the total current being drawn. It has to be connected in series with the main supply.

The voltmeter measures the voltage span from + to gnd. So connect the other lead to chassis ground.

The fuel sending unit is a variable resistor (potentiometer or rheostat depending on your preference). The fuel gauge is basically another ammeter. It measures the current flowing through it as the sending units resistance changes. As I remember the resistance goes higher as the fuel decreases. I don't have my wiring diagram in front of me but one wire supplies the gauge (probably the green). Another wire from the gauge goes to the sending units variable resistor, and then gauge measure the current flowing through this path.

[64Blue]

OK. Got the fuel gauge fixed. Ended up just flipping the wires ( green with black and the green wire).

Now, off to look at the voltmeter. No issues with shorting if I go to ground?

Re: ammeter. Too bad!

Also, when folks rewire the chassis harness, does it seem that there is an excess of wire after the harness splits off to the left and right rear brakes lights, signals, etc?

[RoverForm]

Just swapped out my gen for 90A 12SI alt last week. I also did not see the amm pegged before I disconnected it. Wanted to replace the amm with the period correct voltmeter, though I hear they are impossible to source. May just install a NOS temp gauge instead.

In the mean time I've installed an LCD voltmeter and the alternator pushes 14.3v at revs.