Can anyone diagnose this:
Smiths electric temp gauge reads fine at idle then needle goes to dead cold almost immediately as revs go up from idle?
What shld i be looking at?

Thanks.

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Now with 2 extra ports!

Possibly the instrument voltage regulator, it is suppose to supply a steady voltage but they are often effected by vibration esp when they are stuffed. Is your fuel gauge also playing up?

User "Wombat" on here used to make a tiny electronic version which is much better than the old mechanical regulator.

Other possibility is the actual gauge has a fault and vibration is causing it to play up.

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68 Morris Cooper S Mk1 (*ex 78 1275 LS 4th last built, 70 Morris 1500 OHC & 70 MiniMatic)

Thanks for the reply.

Thought it might be the stabiliser but the Fuel gauge works fine.
Ill try another gauge and see what happens....

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Now with 2 extra ports!

I guess also check all the earths and connections.

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68 Morris Cooper S Mk1 (*ex 78 1275 LS 4th last built, 70 Morris 1500 OHC & 70 MiniMatic)

I assume the coolant level is fine and there are no air bubbles in the system? Thermostat is working too?

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Try the female terminals for tightness on the males of the voltage stabiliser.

Is the car moving

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1960 Morris Mini Minor

Yes.

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Now with 2 extra ports!

Also make sure you have the same 10 Volt feed from stabilizer feeding the fuel and temp gauge. Test with an analog Volt meter on both gauges you should have the same 10 V on both. With an analog meter you will find that the voltage flicks up and down and not a steady 10 volts unless you have an electronic stabilizer which should be spot on 10 V. If the voltage goes past 10 Vols get a new stabilizer. With the temp gauge you should get the gauge to go off the scale by grounding the sender wire with key on. I use a gauge tester at the correct scale of resistance through the whole sweep.

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DID I MENTION THAT I AM THE BEST SUPPLIER FOR MINI ELECTRICAL PARTS AND REPAIRS?
"Let us remove your "SHORTS"

Thanks!

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Now with 2 extra ports!

Is it wired in the stabilizer the right way

More info Rob? As far as I know it is, but open to more information.......

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Now with 2 extra ports!

I think you may have cold air getting into the gauge. Are the corks in the back of the gauge?
Alternatively a bad earth to the engine.
If the reg was going high, the temp would go high.
If the reg dropped out the fuel gauge would drop out.

But i may well be wrong and i'm allowed to be because this is a forum

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1960 Morris Mini Minor

You can check this out by taking the car out of gear at speed and coasting. The revs and vibrations drop away, and then there's just the wind getting through the gauge.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I remember a well known mini mechanic struggling with this issue to the point of distraction.
He drove a poor van up and down the road in front of my work over and over until he finally relented and turned in to my drive. He didnt want to believe me but was so frustrated he had to begrudgingly give my solution a try....
A bimetal strip deflects on the basis of heating or cooling two dissimilar metals.

It may be something else. Whatever you do dont buy a new sender!

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1960 Morris Mini Minor