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TR 3 Temp Guage Capillary Tube

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mountainman

mountainman

Jedi Trainee
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Just got my temp gauge back from being rebuilt and was getting ready to install. My questions is how careful do I have to be about bending the line. I thought I read somewhere that the line has mercury in it and do not want to crimp it.
Thanks
Greg
 
The bulb and tube are filled with ether, not mercury. Kinking the line might cause the tube to crack, which would let out the ether and put you to sleep! :laugh: The coiled wire around the tube is there to (hopefully) prevent this from happening.

A reasonable amount of care is all that is necessary. Be sure to check out how the tube is run and coiled at the back of the engine. It's coiled to prevent vibrations and engine pitching from breaking it. I'll see if I can dig out the diagram if you don't have it.
 
Here's a diagram of the capillary tube routing.
 

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That about covers it. You might wrap around a juice can or such for that 3-turn coil just before it enters the firewall. I have heard lengthy (and heated) debates about the correct radius of that coil.

Also, I always use anti-seize on the fitting that secures the tube to the thermostat housing. Dissimilar metals there can make it difficult to undo years down the road.
 
Geo Hahn said:
Also, I <span style="font-weight: bold"><span style="font-size: 12pt">always use anti-seize</span></span> on the fitting that secures the tube to the thermostat housing. Dissimilar metals there can make it difficult to undo years down the road.
Click to expand...
:iagree:

BTW, I believe it's petroleum ether, not the same thing as anesthetic ether. Still not something you'd want to drink, and I imagine enough of it would still put you to sleep (perhaps permanently), but there is also not enough of it in the gauge to worry about IMO.

The main concern is that letting it out will render your freshly rebuilt gauge useless until it's rebuilt again.
 
I also agree about the anti-seize. It's a "must do" step during the installation.
 
Hi Greg, If you look at the picture of the routing of the wire to the gauge, you notice that under the dash it is in a circle. What is not in the picture is the heater core and the wire wrapes around the heater core. In looking at the picture it does not show the heater. Good Luck, Bill C. Mesa, Az.
 
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