• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!

    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR2/3/3A TR3A tired temp gauge

RonR

Jedi Trainee
Country flag
Offline
Folks,

What is the likely causes for a capillary tube temperature gauge to stop working, and is it repairable?
The is a1.5-inch long section where the outer "coil" is missing, but it use to work even with that is.

Thanks.
Ron
 
I think that coil is just there to help prevent kinking as the line is bent.

The usual failure mode is a leak - the ether inside the tube escapes.

Can be fixed, even possible as a DIY project though I have yet to attempt it. Certainly rebuildable by any of the usual gauge shops.
 
If any of the solder joints fail or the capillary tube fatigues and develops a crack the ether trapped in the expansion bulb and tube will leak out and the gauge stops working.

They are repairable either professionally or as a DIY project. The only caveat against a DIY repair that I will make is as follows. IF the gauge dies where the needle is not resting on the lower stop peg, then more is required than basic repair. Such gauges should be left to the pros.

If on the other hand the needle is resting on the lower stop peg and the gauge just stops working... use the DIY repair method discussed in the link below. HOWEVER, I suggest you use dry ice for the repair instead of the salt/ice cold bath. Dry ice cooling is much colder, cleaner, and does not result in any possible corrosion of the capillary tube's protective spring.

DIY Gauge Repair Link
 
If you need it rebuilt, I recommend Moma in Albuquerque. I visited there a couple of years ago and got to watch various repairs, including a rebuild of a capillary temp gauge. They have the expertise to do a really nice job.
 
I used the instructions that Doug's link refers to with great success, even with my trembling hands.
I really believe, if I can do it, anyone can.
 
Back
Top