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TR2/3/3A TR4A Gauges in a TR3A?

karls59tr

Obi Wan
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I was thinking of removing the speedometer from a 4A that is under resto and won't be going anywhere soon with the plan to repair the 3 Speedo in the winter months. What would the issues be. Is it doable?
Also... I have a dead fuel gauge in the 3. Would I be able to swap in the 4A fuel gauge? Different ground polarity....reverse the leads? what about senders?....could I make the 4A sender work in the 3 along with the 4A gauge. Am I looking for trouble here or could it work? :smile:
 
I believe the 4A speedo should drop right in. The calibration may be a bit different, but probably not enough to worry about unless one or the other had a 4.10 rear axle.

The gauges don't care about battery polarity, but the 4A gauge will need a voltage stabilizer (and aftermarket stabilizers do sometimes care about polarity). It will also need it's own sender, as the TR3 sender works backwards to TR4 and later. Sorry, I don't know about installing a 4A sender into a TR3 tank. ISTR the 4A gauge will also need it's own light, if you want to see it at night.
 
And I'll add (if it matters) the 4A gauges have the needle the opposite direction from the 3 so unless you do all four it will look very mix & match.

There is a 4 digit number (small print) on the speedo -- it is the number of times the cable turns in a mile. If it is the same or close on the two speedos you are looking at then you should be okay.
 
"The gauges don't care about battery polarity, but the 4A gauge will need a voltage stabilizer (and aftermarket stabilizers do sometimes care about polarity)."

Where would the fuel gauge ballast resistor be located on the 4A?
 
What ballast resistor? The original voltage stabilizer is a thermo-mechanical device, not just a resistor. Aftermarket replacements are frequently solid state voltage regulators. The TR4 had it mounted near the hood release under the dash; and later cars had it mounted on the back of the speedometer. But I'm afraid I don't recall where the 4A had it.
 
Passenger foot well, up in the right corner. Many a foot in the autocross with passengers knocked it off.

Just remembered, I have a full set of TR3 gauges somewhere, the water temp gauge, but has a broken tube, right at the gauge.

Wayne
 
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Just looking at Jay's picture brings up a question in my mine. Why in the H... did they change the hood pull in the TR4A and TR6 to the other side and snake it around so much it will always be hard to pull and many have I seen with the plastic broken off????

Wayne
 
Just looking at Jay's picture brings up a question in my mine. Why in the H... did they change the hood pull in the TR4A and TR6 to the other side and snake it around so much it will always be hard to pull and many have I seen with the plastic broken off????

Wayne

Wayne,

The pull is in the same place on the TR4 and TR4A (passenger side). Did you mean just on the TR6?

Scott
 
Of course it is. Early in the morning for the brain to be at full speed. Thankls,

Wayne
 
I always found it amusing that they abandoned the remote hood latch on the TR2, then apparently brought it back later at the market's insistence. Of course, having the hood open from the rear makes the latch a whole lot less critical!
 
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