The temp gauge tube is filled with a chemical that manually moves the needle as it warms up and expands. I believe it is ether but it may be something else. It is not uncommon for the tube to be bent and cracked and the chemical leak out. There are specialists who restore these gauges and some hobbyist that have repaired these themselves and posted the process. It can be dangerous to do it yourself so goggle the options. The gentleman that posted the process on the AACA site goes by Ply33.

Good luck

Dave

A suggestion from a friend with lots of old cars, Williamsons Instruments.  Just talked to Ron, the owner, and he can repair my temp gauge.  I did a lot of searching on the internet with no luck, so I emailed my friend.  Ron said it takes about 2 weeks and he charges $295.  In a way that seems a little pricey, but what else am I going to do?  Besides, we need to support these folks who are willing to take on these unique projects.

Ken

@bowtiefan  Ken, Is your car a Master or Standard? I have some NOS accelerator rods that are not identified. I will be glad to help if you can describe the one you need. Temperature gauges show up in eBay pretty often. NOS ones usually sell for less than the repair price you were quoted. Text me at five seven three eight six four six five three nine with some info about your accelerator rod.

Mike