Gauge questions

[Supermike]

Now that I have my dash lights and flashers working, next up are my gauges. I've searched the site and haven't exactly found anything to answer my questions, so here it goes:

First, my fuel gauge appears to be working fine. When it's empty, it's empty. Filler 'er up, and it's Full. No questions there.

Second, my temperature gauge *appears* not to work. I say "appears" because the needle sits below C and pretty much stays there, even after 5-10 minutes of driving. As I understand, the fuel, temp, and oil gauges utilize the same voltage regulator. Is that correct?

If it is, then with regard to my temperature gauge, is the problem most likely the thermostat, or the sending unit? If so, where is it, and how hard is it to replace?

My oil pressure gauge hangs out around the "i" in "Oil". It moves like 1/8 inch toward H from time to time, so am I to assume it's working? Where would it be hanging out if it were NOT working?

Finally, my ammeter pretty much sits right in the middle of the gauge, too, maybe slightly toward the right. I'll be honest and say I've never really understood this one, or I've at least forgotten what I knew. What exactly am I watching for on this gauge, how do I know it is working, and when should I be worried?

THANKS!!

[71 LONG BED]

First, my fuel gauge appears to be working fine. When it's empty, it's empty. Filler 'er up, and it's Full. No questions there.

Must be working.

Second, my temperature gauge *appears* not to work. I say "appears" because the needle sits below C and pretty much stays there, even after 5-10 minutes of driving. As I understand, the fuel, temp, and oil gauges utilize the same voltage regulator. Is that correct?

If it is, then with regard to my temperature gauge, is the problem most likely the thermostat, or the sending unit? If so, where is it, and how hard is it to replace?

Check the sending unit. It is right on top of the intake manifold in front. It is a small screw in fitting with a wire plugged into the top. They are $5 so it's worth replacing, and is most likely the problem. To check, remove the wire and touch it to the block to ground it. The needle on the gauge should go all the way to the top. If not then it must be the wire or the gauge. I've never heard of the gauge going bad though. It usually is the sending unit or the wire.

My oil pressure gauge hangs out around the "i" in "Oil". It moves like 1/8 inch toward H from time to time, so am I to assume it's working? Where would it be hanging out if it were NOT working?

These gauges are for referance only so as long as it isn't to low or to high, it's OK.

Finally, my ammeter pretty much sits right in the middle of the gauge, too, maybe slightly toward the right. I'll be honest and say I've never really understood this one, or I've at least forgotten what I knew. What exactly am I watching for on this gauge, how do I know it is working, and when should I be worried?

These don't seem to ever move. I was told a long time ago, if it isn't moving it means it's working. Maybe someone has more info on this, I'd be interested to know myself.

[Supermike]

Thanks... is the "sending unit" also know as the "temperature switch"?? Or is it the "Engine Temperature Sensor"?? Autozone lists both...

They also list a "Coolant Temperature Sensor". They only stock the "temperature switch", though...

[71 LONG BED]

Probably "Engine Temperature Sensor", if I had to guess. I circled it in the picture. That is a 302.

[Supermike]

Thanks again. Crud... autozone does not list that part as available, and I can't find it on Napa's site either. For some reason, Oreilly only lets me look up volkswagon parts (does not list any other make to choose). Cant find on Advance's website either.

Engine is a 352... anyone know a part #?

[68F250]

I was in the same boat with my '68 and had to special order it, Motorcraft SW-552, pn C6DZ-10884-B temperature sending unit. If you try to use one from a later year it will read too high.

The insulator ring around the connector is red, Ford used a color code for them.

[bluef250]

Sound like all your gauges are working. My temp gauge used to never get above C until I fixed it. I actually had to put cardboard in front of the radiator to get any interior heat. No movement on the charge (amp) gauge is common. Ford used a shunt - 2 wires in parallel - to measure the difference in voltage between the battery and the alternator. The difference in voltage creates a current. The larger wire carries almost all current. The smaller wire goes to the gauge and carries almost no current. I think the shunt can be "made" more responsive by installing a larger gauge wire (with 3 amp fuses at both connections) and disconnecting the OEM wires. This question has been discussed on many different Ford sites and several times here - Search for shunt - if you want more information.

[Supermike]

I was in the same boat with my '68 and had to special order it, Motorcraft SW-552, pn C6DZ-10884-B temperature sending unit. If you try to use one from a later year it will read too high.

The insulator ring around the connector is red, Ford used a color code for them.

Thanks! So that same part number sending unit will work on my '67?

[68F250]

Yes, going from memory I believe the application is from a certain serial # in '66 all the way thru '68.

[Supermike]

Excellent... now, where do I order it from? A Ford dealer's parts counter? Nappy Auto Parts?

Thanks for the info on the ammeter, bluef250... I'll look that up and see what I can learn.

[68F250]

I ordered thru Ford and of course got raped.

Google the #, there's quite a few places.

[68F250]

Yeah I paid around $50 for mine 10 years ago. Don't have any experience with the knock-offs but for $12 I'd take the gamble, jmo.

[71 LONG BED]

$50!!!! Are you F'ing kidding!? I paid 5 bucks and change, and it works fine. I got mine at Advance Auto. Holy moly!!! I still can't believe it, 50 bucks...

[71 LONG BED]

Here is a link to Advance. My buddy works behind the counter and must have given me a discount, but it is still only $12. Let me know if the link works, I was logged in under my username.

[68F250]

Yeah $50! and believe me I tried every possible year sender and brand from every auto supply store before I bit the bullet.