10 replies to this topic

[box200]

Hi there.

On my classic Mini Clubman 998cc from 1975 the temperature gauge is simply marked as ( C )old, ( N )ormal and ( H )ot but I was wondering does anyone know what the actual temperature difference (in degrees Celsisus) is between the C and N or between N and H?

The reason I am asking is because I suspect my mini has the wrong thermostat fitted.

It should be a 82 degree Celsius thermostat but it was changed a year or so ago. Before the new thermostat was fitted the car always kept to the ( N )ormal mark on the gauge and never moved no matter how hard the car was driven but now it tends to creep up to just under the red mark of the ( H )ot before returning to ( N )ormal (and so the process of heating and cooling goes on). I am thinking that maybe an 88 degree Celsius thermostat was fitted in error in which case would the differnce between the N and H marks be around six to eight degrees?

Thank you in advance for your help.

[Wil_h]

What you need to 'calibrate' the gauge and sensor is some boiling water and some iced water or just a decent thermometer.

Take the sensor out of the block leaving the wire on it' then you need to run a wire fom the earth of the car to the body of the sensor. Dunk it in some water that you know the temperature of (either boiling 100deg, iced 0 deg or any other using the thermometer) then see what the gauge reads.

Easy.

Another possible way is to use an infrared sensor and take a measurement of the block when the engine is hot. Not sore that this would 100% reflect the internal water temperature though.

[box200]

What you need to 'calibrate' the gauge and sensor is some boiling water and some iced water or just a decent thermometer.

Take the sensor out of the block leaving the wire on it' then you need to run a wire fom the earth of the car to the body of the sensor. Dunk it in some water that you know the temperature of (either boiling 100deg, iced 0 deg or any other using the thermometer) then see what the gauge reads.

Easy.

Another possible way is to use an infrared sensor and take a measurement of the block when the engine is hot. Not sore that this would 100% reflect the internal water temperature though.

Thank you for your reply however I was in fact referring to the calibration (is that the right word?) of the actual dial on the instrument panel. If the Normal mark on the instrument dial is 82 degrees what temperature (in degrees) are the Hot or Cold marks? If my car is incorrectly running an 88 degree thermostat I assume the temperature gague would obviously read higher than the Normal mark?

[mike.]

Use wills method to find out. Get a pot of water thats 82 degrees, put the sender in it and see where the gauge reads.

[box200]

Use wills method to find out. Get a pot of water thats 82 degrees, put the sender in it and see where the gauge reads.

Oh, now I see. Sorry my mistake!

I would have thought the operating ranges of the sender would have been published somewhere though so we did not have to work it our for ourselves?

[mike.]

Not sure really....

A lot of people don't even bother with the standard gauge as they're not even that accurate anyway, you can fit a proper gauge fairly cheaply with an old smiths or a tim gauge.

[box200]

Not sure really....

A lot of people don't even bother with the standard gauge as they're not even that accurate anyway, you can fit a proper gauge fairly cheaply with an old smiths or a tim gauge.

Thanks for you reply.

I am mostly interested in keeping the car as orignal as possible. Until the new thermostat was fitted I had no problems with my Mini and the gauge always read Normal no matter what but as soon as the new thermo went in the gauge rises and falls like a yo-yo. There must be something wrong somewhere?

[Wil_h]

Not only is it unlikely to be published what temperature the gauge is really reading, from my experience they all read differently anyway. the only way to find out is by doing the above really.

[box200]

Not only is it unlikely to be published what temperature the gauge is really reading, from my experience they all read differently anyway. the only way to find out is by doing the above really.

I guess you are right there, back in the 70's technology was not as accurate as today.

However am I right in saying that on a Mini of that era the temperature would be expected to stay steady and never move or should I expect it to rise and fall as the thermostat opens and closes?

[Wil_h]

Mine moves around plenty, depending on lots of things. speed, going up a long hill, sat in traffic, general temperature.

I have a secondary temp sensor that I can see the actual temp on my laptop. I have a 88 stat, but it never runs at that , much cooler. I do have a front rad though, not a side mount.

[mini13]

I have a capipery smith gauge in one of my cars and it varies loads, I can tell its lieing as I have an ecu that reads the temp as does Will, the spths gauge can move over 10 degrees straight away just by stomping on the throttle, its crap!

Ironically another car I have has a cheap tim gauge and that seems really good,not been able to check that agains an ecu though.