[Chiefkey]

I've been following the discussion on amp gauge connections on a previous thread and was wondering about possible fixes for the overheating problem.
I'm getting ready to send my wire harness in to be rebuilt and was wondering if I should request that they increase the wire size for the amp gauge and have high temp ring connections used instead of the push on blade clips. Would this make the amp gauge itself a weak point in the circuit ? How much current can be passed safely through the gauge ? Should I consider placing a cut-off relay in the source wire to be able to de-energize that circuit in the vent of a problem or when the vehicle is parked ? Anyone have a thought they'd like to share ?
Thanks,
JK

[Peter Serio]

One thing that every '63 owner should do is pull the instrument cluster and inspect the amp gauge plug-in as well as the black cardboard insulator underneath the 2 brass tabs.


I would re-think a better way to insulate those threaded studs against the silver back-plate of the amp gauge (which is ground) and then solder ring end eyelet terminals onto both the red and the yellow wires. Protect the exposed metal of the ring ends using shrink wrap further down onto each wire and then using the original nut(s) and 2 new insulating fiber or nylon washers bolt those 2 wires back onto the studs.

As a quick-fix I would install one of those quick-disconnect battery cable ends into the "-" side of the battery terminal and disconnect the battery whenever you put the car into the garage or you will not be driving it for more than a day or 2.

As far as adding a 30 or 35 amp Heavy-duty cutout relay in either the red or yellow wire perhaps George K could chime in here with a suggestion of how that might work?

[tekuhn]

I took your advice and pulled my dashboard to inspect my wiring. The nut on the yellow connection was pretty loose and it was pretty dark like it had been getting hot. I went ahead and totally disassembled the gauge, including removing the threaded studs from the brass. There was some corrosion where the head makes contact with the brass. I cleaned everything well and added an inside star washer between the head of each stud and the brass contact. This forces the teeth to dig into both pieces to help ensure good conductivity. For your suggestion about replacing the rear thin fiber insulator, I asked my son to 3D print a new one out of polycarbonate - 1.4mm thick. I then also put another pair of inside star washers between the ring connectors and the nuts. All wire connections are soldered. I made the leads to the gauge as a pigtail that I terminated with an EC5 connector. I then put the matching EC5 on the existing red and yellow wires from the harness. EC5 connectors are rated up to 120amps continuous, so I feel pretty confident it will do well in this application. I coated all connections with silicone grease to prevent oxidation. The final step will be to install a 40amp inline fuse immediately at the starter solenoid where the yellow wire begins. This will ensure that virtually everything downstream will be protected in the case of a major short circuit. I used 10awg wire. Couldn't find any yellow, so used black and red.

I took the opportunity to use some florescent red paint to freshen up the needles on everything. The sun had faded them almost white. I wanted to try to clean the gauge faces, but was afraid I would damage the stenciling, so I left them alone.

[Peter Serio]

[QUOTE=
I took the opportunity to use some florescent red paint to freshen up the needles on everything. The sun had faded them almost white. I wanted to try to clean the gauge faces, but was afraid I would damage the stenciling, so I left them alone.


Looks real good, one thing touching up any old gauge set (the pointers) using brush paint is tricky. When you brush paint onto lightweight aluminum pointers you are adding weight. The factory spray painted those pointers.



Adding a tiny bit of extra weight to the amp gauge or the fuel gauge pointers on your car, I do not see a problem with. When you add weight to a speedometer pointer by putting more paint on the long side you will affect the speedometer's reading. The pointer and speed cup (as an assembly) are balanced to static neutral. The weight of the original spray paint on the fluorescent orange/red part of any older (cable driven) speedometer is part of that balance. When you over-paint the orange/red color with additional paint, especially brush paint; on top of the original paint that upsets the balance which will lead to an error in reading MPH.

The pointer and speed cup of any old speedometer are featherweight objects.

When the pointer comes up from the zero mark, around 25 to 30 MPH that pointer is showing basically as a horizontal line. Any extra weight on the long-thin side of that pointer will cause the speedometer to read in-error less that true speed. Once you get up to around 60 or 65 MPH that pointer display is vertical. Extra weight on the pointer when your are at 60 or 65 MPH is not affecting the reading in error as much as it is at 30 MPH. A painted pointer, the error will be basically reading less than actual speed (assuming that the speedometer was reading 100% true prior)

Weight from added brush on paint will make the speedometer read approximately 5 MPH less that true at around 25 to 30 MPH road speed. At 60 to 65 MPH the error will be much less to even negligible it may be only +- 1 MPH.


I see that orange/red color for sale all the time in a tiny glass bottle with a small (one-use) paint brush. It is fine if that's what you want to use but the people who sell that stuff probably have no clue that adding weight to the pointer affects a speedometer the way that it will on a 50+ year old car.

[tekuhn]

Interesting information. I had not thought of that. The speedometer read about 2 mph too fast anyway, so maybe I’ll like the result! I suppose it will read too fast on the downhill side after 60.

Is this the standard configuration for the ignition resistance wire? Just making sure nobody has messed with it.

[tekuhn]

Never mind, I found it. I have never seen one before. It’s the cloth covered wire in a factory splice to three purple wires.

[tekuhn]

I got things together far enough to start the engine, and the fluctuation in the voltage seen as flicker in all lights, but most noticeable in the dashboard illumination lighting, is completely gone! Thank you for bringing this issue to my attention!