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TR2/3/3A TR3 Temp Gauge Upgrade?
- Thread starter karls59tr
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TR3driver
Great Pumpkin - R.I.P
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Most 2" mechanical gauges will work fine; found mine at the local FLAPS for about $20.
Sender screws right into the thermostat housing as the original did; all I needed to do was hook the bulb wire into the dash light circuit.
But unless your gauge is broken in an unusual way, I'm not sure it would be any better. Any gauge can only read the temperature at the bulb/sender.
Sender screws right into the thermostat housing as the original did; all I needed to do was hook the bulb wire into the dash light circuit.
But unless your gauge is broken in an unusual way, I'm not sure it would be any better. Any gauge can only read the temperature at the bulb/sender.
martx-5
Yoda
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I just had to buy one at my local FLAPS because the repair I did to my original gauge two years ago gave out. A small split in the solder joint let all the ether out. However, I paid $35 for the FLAPS gauge. I appears that the prices are going up on these, as they used to be in the $20-$25 range. It was a direct bolt-in.
martx-5
Yoda
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I believe that the problem that you will run into is the threads in the thermostat housing where the sender screws into. With the mechanical gauges, it seems that the universal fitment is a 5/8"-18 straight thread, not a pipe thread that the electric senders seem to come with. My gauge came with adapters so the 5/8"-18 thread could be used with NPT applications. I don't know if they make adapters to work the other way around.
If I'm not mistaken, the TR4 electric sender is a 5/8"-18, but it would then be necessary to mate it with a TR4 gauge and voltage stabilizer.
Here's a couple of pages of mechanical temp gauges from NAPA They should be able to get you one pretty quick if they don;t have one in stock.
Edit: Being that you asked, a mechanical temp gauge basically reads pressure from the expanding fluid in the gauge, just like the oil pressure gauge. This changes the shape of the Bourdon tube in the gauge and this moves the needle. The electric type generally has a bi-metallic spring that gets heated by the amount of current flowing through it determined by the change in resistance in the sending unit. This heating and cooling of the spring changes it's shape, and moves the needle. There are other types of electrical gauges that work more like a voltmeter, again using the variable resistance of the sender.
If I'm not mistaken, the TR4 electric sender is a 5/8"-18, but it would then be necessary to mate it with a TR4 gauge and voltage stabilizer.
Here's a couple of pages of mechanical temp gauges from NAPA They should be able to get you one pretty quick if they don;t have one in stock.
Edit: Being that you asked, a mechanical temp gauge basically reads pressure from the expanding fluid in the gauge, just like the oil pressure gauge. This changes the shape of the Bourdon tube in the gauge and this moves the needle. The electric type generally has a bi-metallic spring that gets heated by the amount of current flowing through it determined by the change in resistance in the sending unit. This heating and cooling of the spring changes it's shape, and moves the needle. There are other types of electrical gauges that work more like a voltmeter, again using the variable resistance of the sender.