Lotus Bulb Type Tempeature Gauge Repair
The temperature gauge in a Lotus car with the bulb type of sender has ether in it which is very flammable. You must NOT use OPEN FLAME IN SOLDERING THIS.
You can find instructions on how to repair a gauge similar to the one the Lotus cars at http://www.sunzeri.com/Stearman/tempgauge.htm
I have no connection with this website and cannot vouch for it other than to so this is where I found the directions for doing this. Use this link and the instructions below at your own risk!!!!
Repaired my temp gauge about an hour ago. It works great.
Took me about an hour of messing around while sort of listening to the Super Bowl in the other room. I had bought a Sunpro gauge from Autozone.
Made the bath of ice and salt and stuck the bulb of the Sunpro gauge into the bath to allow it to cool down below 37 degrees which is the temp ether turns to liquid.
I then first cut off the spun wire guard on my broken gauge, then using a dremel cut off wheel, I cut the tubing. I had to ream it out just a bit.
The hole is really small, so small that you can barely fit a very small sewing needle into it.
Then using 3/32 brass tubing, I cleaned it all up and soldered the 332 tubing onto the capillary tube of the Lotus gauge.
I used about two inches of 3/32 brass tube pushing the gauge capillary tube in about half way.
I could look into the 3/32 tube and still the hole was open in the Lotus gauge tube.
I then looked at the temperature on the thermometer I had in the ice salt bath and it was 32 degrees. I then cut away the wire guard (using a set of diagonal cutters) on the Sunpro gauge.
The capillary tube on the Sunpro gauge was smaller than the capillary tube on the old Lotus gauge, so I first put a piece of 1/16 inch tubing in the 3/32 tubing I had put on the Lotus gauge tubing.
I soldered it up. I then put the small capillary tube from the Sunpro bulb that was in the bath into the 1/16 tube and soldered it up.
I smelled a tiny bit of ether as I did all this.
I used a very low temp circuit board soldering gun and everything was fine.
Above find the pictures of the test. It is important to not let the bulb hit the bottom of the pan. Just into the boiling water,
You do not want to over heat the bulb by letting it touch the bottom of the pan or really the pan in any way. The pan is hotter than boiling water.
100 degrees centigrade. Right on the money.