The Fuel & Temp Gauges on my '53 F-100 don't work. The Fuel is at E and the Temp at H. I applied 1.5 v to each but no movement. There is continuity on the wiring to the sending units.

I want to be frugal (cheap) and only replace what is necessary. Any other way to check these or does it look like it is the gauges?

The oil & battery gauges function.

Thanks.

 

Check to see if power is getting to the fuel sender and the temp sender. What engine is this? If it's a flat V8, the "excessive heat switch" (on the left cylinder head, with two terminals) could be failed.

 

It is a 239 flat head 8 and I'm jes gettin into this stuff.

I've got 5.91 v on one side of the fuel gauge and .01 out. There was .01 at the fuel sender.

5.91 v on one side of the temp gauge but 0 v on the other side and nothing at the sender.

Does the oil gauge work on the same principle at the temp gauge? i.e. To trouble shoot, could I hook the temp senders up to the oil gauge? Could I hook the fuel sender to the oil gauge?

 

Power is applied to the gauges up at the gauges then flows to ground through the sending units. Variable resistance in the senders is what gives the indication.

So let me expand on what Ross said. Turn your key on and go out to the temp sending unit (it's going to be much easier to get to that the gas sending unit on the 53), disconnect the wire from it and check from that wire to ground to see if you get a 6 volt reading (I'm assuming your truck is still OEM 6 Volt Pos Ground, right?). If no reading, you are not getting power to the gauges. It comes from the "ACC" stud on the ignition switch.

Check to see if someone has installed an inline fuse holder to the power wire to the gauges, or has a fuse block for the acessories. If so check the fuses

If you have a 12 volt conversion get back to me and let me know - different things to look for.

 

Thanks for both sets of advice. The truck is still the original 6 volt system. There is no voltage at the senders so I figure, from your description, the guages are bad.

The only place I've found 6 volt gauges (Obsolete Classic Auto Parts)provides temp senders with the temp gauge but not the fuel gauge. I'll try just the fuel gauge to save money & purchase a sender if that doesn't work.

Thanks again for the advice.

Howie

 

Another question: does your oil pressure gauge work? Or do you have an idiot light for that?

What it means if you have no voltage at the sender is that either the gauge is fried, or there is no power getting to it - bad or no wires.

Power should flow when the key is turned on and it should flow from the "ACC" terminal of your ignition switch to one of the gauges - usually the temp gauge. Then there should be either a metal shunt or a jumper wire connecting the "power in" side of each gauge. You need to check to see if the there is power coming out of the "ACC" post of your ignition switch when you turn the key on, then you need to check that there is 6 volt power going to each gauge.

If not, that needs to be fixed. If there is, then it's possible the gauges are fried. I have a whole bunch of 51/52 gauges that have the same internals. I can send you a temp and a gas gauge if you want to change the faces and backing plates with the ones from your gauges - it's VERY easy to do!

Check for power first - to EACH gauge!

 

Thanks Julie. We had a combination of a computer virus and snow storm this week so I’m slow in checking in.

The truck has an oil gauge and it works.

There is voltage on one side of all gauges but the fuel & temp gauges have only .01 or 0 respectively on the other.
There is continuity on all lines and the same voltage reading (.01 & 0) at the fuel & temp sensors.

I would love to get my hand on a temp & fuel gauge and if you say changing the face is easy, I figure I can handle it. Let me know what I need to do.

I did check the fuel sender today with an ohm meter. It fluctuated between 8.3 & 8.6 ohms at first. Then I added 5 gals of fuel. While adding the fuel at first the meter steadily rose to about 9.1 and then when all over the place. After the fuel had settled, in fluctuated between 8.1 & 8.4 ohms.

Does that tell you anything bout the sender.

Thanks.

Howie

 

Well it sounds like everything is working ok except the two gauges. It appears the shunt is still in place providing the bridge for power. One last question: If you turn on your ignition, and have voltage at the gauge, if you hook a jumper wire to the outbound stud of the gas or temp gauge and touch it to ground for about 3 seconds, does the gauge needle move up or does it just stay put? If it moves chances are they are still good. If it doesn't move it's fried (or stuck).

Send me a PM with your address and I'll send you a gas and temp gauge. But check the gauge by grounding it first.