Thermal Sensor

[simmitc]

Does anyone know of a sensor that will screw into the head (1098) like a sender for an electric temperature gauge, but insetad of varying resistance with temperature, will simply be "open" up to 95 degrees, and then "closed" at higher temperatures. The aim is to get an unobtrusive high temperature warning light rather than having to resort to a gauge. Thanks in advance for any ideas.

[autolycus]

Wander round your favourite scrapyard looking for poverty-spec cars that don't have temperature gauges. Many of them will have warning lights, and these may be operated by switches. ISTR that the Peugeot 106, for instance, has this arrangement. You may have to do a bit of fiddling with thread adapters. Or find a car with an electric fan (most of them).

Life was much simpler when all you had to do was watch for flecks of antifreeze (or dirty water) on the windscreen because your engine was boiling like a kettle and your radiator cap O-ring had perished.

Kevin

[Jefftav]

Didn't some Morris's have a warning light in the speedo when the car overheated the light came on?

[M25VAN]

I think you might find the problem is getting something that small to fit in the block. Try the intermotor website, loads of temp sensors and switches but I guess any of the small ones may be metric sized. How about an 'external' sensor? I found this site..... http://www.coolantalarm.co.uk/index.php ... roductId=7. Sensor just fits under a cylinder head nut or wherever you want to keep an eye on. Bit pricey, might find it cheaper elsewhere. They even do a low coolant level warning version as well.
Just looked a bit more and they have a custom sensor section....http://www.coolantalarm.co.uk/index.php ... t&catId=15... although they look like coolant level detectors, maybe send them an email.......
Just looked a bit more again and found this....http://www.coolantalarm.co.uk/index.php ... oductId=49... temp display, alarm and it can switch on an electric fan. All for £55!

[twincamman]

I know that poverty-spec Ford KAs have them (might even be imperial thread?), and all the current Vauxhall range have warning lights instead of gauges.
Just a thought though, how about an electric fan switch that screws into the rad? Wire is up with a live feed and take the other terminal to the light.

[bmcecosse]

Aye - but it won't 'screw into' a Minor rad - without soldering in a boss first. Sounds like an awful lot of work to me - and a risk point for leaks! It's usually only too obvious when a Minor boils - the brown water and 'steam' splattering on the windscreen is the first sign......

[simmitc]

Thanks for suggestions, worth following up. Agreed that it can be obvious when it boils, but also it can be missed if the bottom hose splits and all the mess is directed under the car on misty day...

[bmcecosse]

Don't worry - you get a wonderful 'hot' smell when that happens - and the heater immediately goes cold. Light would do nothing anyway - since no water there (hot or otherwise) to activate the sensor!