I am currently being told that the first batch could be done December 30th. I may be able to ship a few by air and have them just after the 1st of the year.
Maybe just an idea of what to expect if a 9V battery or other common power source is connected between the two leads. Just looking for some quick sanity check if possible.
Nothing bad would happen. It would light up the LED in the power test position. In the full position it might warm up some but you would have to leave it hooked up for quite a while and the battery would probably run down first. It would not effect function at all.
This may have been covered previously, but why is there a difference between fuel and the other two gauges? I believe nothing, except by how one expects to explain the readings: oil pressure or water temperature is high, but fuel level is also high. I guess fuel level isnât described as âlowâ but empty.
Can I suggest âmid-rangeâ instead of âMâ for fuel, oil and water? A nice trick would be for fuel to show what 4 gallons on the gauge reads, but that would add another step I suppose.
Thank you for the feedback. It really is great to see this through other eyes. This is exactly the kind of question that I struggle with. My thinking was that the Fuel gauge is Marked F for full and E For Empty. The oil pressure is marked in PSI on our Cougars but other Fords also have L for Low and H for High. Temperature always seems to have C for Cold and H for Hot. I think to a lot of people they are looking for literal meaning: the needle reads H or F, C or E. That was what I was trying to get at. I think the instructions on the back take a stab at trying to explain things
As to the 4 gallon mark, that comes into play with the thermistor for low fuel senders. It is completely independent of the gauge reading, depending on the height of the thermistor from the bottom of the tank. As it turns out different vendors slightly varied the position of the thermistor. This could be an entirely different discussion but it seems to be less prone to falsing when it is slightly closer to the bottom of the tank. I guess it is a choice: do you want it to start to occasionally flash when you still have 5 or more gallons, or should it start to flash when you have closer to 4 gallons? I think the later is preferable. I know that back when this was new feature on the Thunderbird that some owners complained about it lighting up to soon.
Donât some Cougars come without low fuel sensors? Your gauge tester can also apply to any FLM vehicle, so there are more vehicles without a low fuel sensor than those that do have it (think of the market possibilities!). Not all low fuel sensors work properly. An owner should want to know what the fuel gauge reads when there is supposed to be four gallons (1/4 tank). However, there are 16, 18, and 20 gallon tanks out there, so that adds to the difficulty.
Why not have 3 columns: one for fuel, and two side by side for oil and water temperature, each with their proper letter markings. I still think âmid-rangeâ is the better choice for the middle reading.
Bill:
Thereâs another issue that youâll have to be aware of. Starting in 1971, Ford changed the connectors at the fuel sending unit from the 90* slip-on connector to a combined signal and ground shrouded molded connector that doesnât allow for your alligator clips to attach to the female sockets. Some years, thereâs a third socket (presumably for a low fuel line). Iâve never noticed the orientation of which socket is which line, as I can rapidly change from one socket to another with the needle probes that I use to test for continuity. To use your gauge tester, you (or the customer) will need to use a #10 bolt or all-thread to insert into the socket and then use the alligator clips to attach to the bolts.
BTW, I will be moving to Tucson next Saturday. I hope in the following few weeks to have a chance to meet you by a short trip to the Phoenix area. I think we have an awful lot in commonâŠ
Randy
Would there be a way to test loose gauges with it?
Would it have to contain a power supply and regulator?
What would I need to test them separated from the cluster?
Would the reading be slightly different on the gauge because the rest of the harness is not involved?
Yes, I was the kid in class that raises their hand a hundred times. These questions may have already been answered and I missed it but I think I read it pretty well. We will see.
Midlife: I am thinking about including a #10 screw but I think it will get lost pretty quickly by most folks. I have the Rotunda tester that has the other types of connections built in. I will have a diagram with the various connectors illustrated in the instruction sheet.
Since 1980:
Would there be a way to test loose gauges with it?
Yes you would need a 12 volt supply and an Instrument Voltage Regulator.
Would it have to contain a power supply and regulator?
Yes.
What would I need to test them separated from the cluster?
No it would probably be easier to leave them in cluster.
Would the reading be slightly different on the gauge because the rest of the harness is not involved?
Only to the degree you have some series resistance in the harness, but that will probably be minimal compared to the variability of every other part of the circuit. These were never terribly precise, highly accurate, instruments. Even fairly modern vehicles are still a bit off. I have driven my F150 for miles when the warning panel shows 0 miles to Empty. (Thank God for this!)
Oh, and the gauges and stock IVR are both adjustable if you do what to dial them in.
Thank you very much. I have many dashes and it would be an advantage to be able to check them pryor to installation or sale. An excellent idea. Outstanding effort putting it all together. Ill take two. And, I guess I could just put a Cougar body up on blocks, fit it with a wiring harness and use it as a test bed for my dashes. Hummm⊠what color test bed do i want? Wait⊠why stop there?
The first 24 have arrived!
The GT-Ford-1 Gauge Tester is now available!
$29.99 includes Priority Mail shipment in the USA
In appreciation of the great feedback, all ClassicCougarCommunity.Com members can use COUPON CODE ccc.com and get $5 off
To order go to https://desertclassicparts.com/product/gauge-tester-gt-ford-1/
GT-Ford-1 Gauge Tester Instructions
For your gauges to provide accurate readings two other things must also work properly. First the Instrument Voltage Regulator (IVR) must supply an average output of 5 volts. Second the sending units for Oil Pressure, Water Temperature and Fuel Level must output the correct values. The Gauge Tester checks for IVR operation, and then substitutes for the senders to supply the correct signal to verify gauge readings.
Connection For Testing
Disconnect the sender. Connect the red lead to the wire you just disconnected from the sender. Connect the black lead to ground, not the sender. Put the key in the ACCESSORY or RUN position. Note: do not leave the key in the RUN position for an extended period of time without the engine running. It may take the gauge up to two minutes to reach itâs final position.
Trouble shooting tip: Most failed gauges read low or nothing at all. Be sure to check that the needle is not in contact with the face of the gauge or bent. It may be possible to adjust low reading gauges. This is a very delicate procedure that should be performed by a professional.
Power Test
Connect the Tester as specified above. Put the switch on the tester in the Power Test position.
The Fuel, Temperature, and Oil pressure gauges are all powered by the Instrument Voltage Regulator. The electromechanical version of this regulator puts out pulses of power that averaged over time are equivalent to 5 volts. Newer solid state regulators provide continuous 5 volt output. The first test of any gauge begins with verification of the power source.
A properly working electromechanical IVR will flash between one and three times per second. The actual frequency is not important, the flashing indicates a working IVR. Solid state IVRs will illuminate the power light continuously.
Trouble shooting tip: If all gauges read high or low this is an indication that the output of the IVR is too high or too low and it should be replaced. Solid state replacements are more stable and not effected by temperature changes. If all gauges are pegged on high first check the IVR ground. The IVR must be grounded to function. If the ground is good, the IVR is defective and must be replaced immediately as the gauges can be damaged.
Position 1 Hot Temp, High Oil Pressure, Full Tank
Connect the Tester as specified above. Put the switch on the tester in position 1 (H F). The high reading for all gauges is the factory calibration point. The design of the gauge makes this the most precise indication of gauge function, and the only actual calibration point used by the factory.
Gauge designs vary but the center line of the pointer should fall between the two edges of the marker line. On some gauges there are two marker lines, the pointer should end up between the two lines.
Position 2 Mid Point
Connect the Tester as specified above. Put the tester switch in position 2 (M). The Mid Point of the gauge is less precise than the High reading. The center line of the pointer should fall within 1/8th inch of the center line of the gauge.
Trouble shooting tip: If your gauge reads correctly in the high position but incorrectly in the middle and low position the gage is either defective or it requires professional adjustment.
Position 3 Low Oil Pressure, Cold Temp, Empty Tank
Connect the Tester as specified above. Put the tester switch in position 3 (L/C,E). The Low point of the gauge is the least precise reading. Begin the test by observing the location of the pointer with the key off. When you turn the key on, the gauge pointer should slowly rise to the Low or Empty marker. It may take two minutes for the reading to stabilize. The center line of the pointer should reach the edge of the lowest marker line on the gauge. Due to the design of the gauge the low reading my fall within a window of 1/8th inch above the lowest edge of the marker line.
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Order placed.
Thanks guys! They will be in the mail tomorrow.
I ordered one too!
Hey Bill, Iâd like to buy one, but, there doesnât seem to be an option to buy and ship if you are outside of the US.
Ordered mine. Thanks for the discount!
My software canât deal with international shipping. I will send you an email. I hope this gets there before Christmas.
Yes, we definitely have some experience with slow and misplaced package shipping.