Ambient temperature gauge

[DrEntropy]

[quote=c.d.s.] They are a bit of a mad/entertaining lot due to the use of such chemicals Cool
[/quote]

*HIC*

Whadda ya mean!?!?! I'm jus' fine!

[mikealdren]

Many thanks to all for the replies. Consensus seems to be that the gauges can be rebuilt and that's good news. It's also good to know that the gauges use ether and not some obscure/unobtainable/banned substance.

An electronic gauge is appealing but I have a lot more to do at the moment.

Mike

[Matt]

This is something I've been working on as I'm an electronics geek, the one I have done works fine, I powered it off my lighter socket and I put the thermistor in the nose. My gauge is deeper than the original so I can't get it to fit in the original smiths casing, but does fit behind the dash fine I've removed it from my car and am going to try to make it smaller.

My Plan is to make a kit to covert broken gauges

I also have a new old stock original that I'm not going to use if anyone wants to make me an offer it's never been fitted and is in A1 condition even has the fitting instructions from lotus and a new smiths gasget.

Matt

[richgilb]

I have spoken to the guys at Speedograph (www.speedograph-richfield.com/) and they say they can repair/refurbish this gauge for 70GBP inclusive of VAT & carriage.

Jeremy

I hope this is still possible, since Spyder reckon they can get them new for ?120....which I thought rather pricey.

[bob_rich]

Hi I am looking at repairing my ambient temperature gauge.

I have stripped it down and checked the required pressure to move it over the scale, the gauge mechanism seems to be quite free and does not jam but the pressure required to move it seems a lot higher than that produced by ether vapour pressure. I found that to read +10C needs 1.4bar gauge pressure and +40C needed 6.1 bar gauge pressure. Ether vapour pressure is much lower than this around 1 bar at 35C and 2 Bar at 56C. Either my gauge is shot but its mechanism is nice an free or the chemical inside was not ether.

Ether is probably fine for water temperature gauges as one is interested only around 70C to 120C temperature range where the vapour pressure for ether is 3 Bar to 10 bar respectively.

Hope this helps and interested to find out what others may have done/found

Bob

[Jentwistle3]

Smiths now makes an electronic replacement!

http://www.smiths-instruments.co.uk/classic

[prezoom]

How timely. I had just found the bulb completely broken away from the tube when I was fitting the Miata headlight retractor motor. Have queried Speedy Cables, but have not received a reply. Looks like a better investment.

[bob_rich]

Hi

I managed to mend my ambient air temp gauge and I wrote up the repair and it was an article in the April 2015 edition of the Club Lotus News magazine. I wrote in a post in this forum back in 2009 that Ether was not (IMHO) the working fluid in the gauge. I managed to fill mine with a Camping Gaz which has a vapour pressure v temperature characteristic close to that required to make my gauge respond quite well in the -10 to +30C region.

It was a bit of a fiddle but proved to be an interesting exercise and is still working over 3 years later.Like yours all the capillary was missing so had to make that up as well

Can let you have a copy of the article if you like -- though the electric one does look quite interesting ! but was not around when I fixed mine

best of luck

Bob

[prezoom]

I finally got a reply from Speedy Cables regarding the electronic ambient temperature gauge. They replied that they could not help me. Tried Merlinmotorsport, which has been an excellent source in the past and they had the same answer. Anybody have any other suggestions where I might be able to purchase one of these gauges?

[JJDraper]

Interesting that Speedycables and Smiths are located in the same industrial estate in Wales. Must be a reservoir of know-how...

However, IMHO an oil temperature gauge is far more useful to the health of your elan than knowing the temperature of the air. If its a bit frosty, then you will know it.. and the air temp gauge will never predict a patch of ice in the shadows. Looks period and is cheaper too.

Jeremy

[Quart Meg Miles]

However, IMHO an oil temperature gauge is far more useful to the health of your elan than knowing the temperature of the air. If its a bit frosty, then you will know it.. and the air temp gauge will never predict a patch of ice in the shadows. Looks period and is cheaper too.

Jeremy

Dead right, and it was the first mod I did to my Elan, eventually fitting a proper socket for it opposite the sump drain plug (instead of fitting through a modified drain plug).

It can't be correct to seal the tube while the fluid is at ice temperature as the empty gauge reading is nearly 40?C, the boiling point of Ether, so it wouldn't be able to suck down to read 30?.

Both water and oil gauges use Ether but an ambient temp gauge uses something else.