8 replies to this topic

[pusb]

A general query now that the weather is starting to get a bit warmer.

 

I sure all of us that use our Mini's in rush hour traffic have noticed the temp gauge slowly climbing in hot weather. Unlike a modern car temp gauge that boringly sits in the middle no matter what, a Mini Smiths gauge can vary massively in a single trip.

 

The question is, at what point do you start to worry that the gauge it too high? At what point does it go from being high because its a hot day but the cooling system is coping, to being a full on overheating problem?

 

If we look at the gauge: 

 

 

Where on there should you start to worry?

 

I have seen mine go round to the yellow line, and the car seemed ok.

 

But should it never go past the red line? Or is it ok to go right round to the blue or purple line?

[ukcooper]

never had any what you don't know don't hurt ya .lol.

 

I believe but I could be wrong it also depends on the temp sensor can affect it massively as well.

 

go for a drive see what I sez and mark the spot

 

go for a spirited drive and mark the spot

 

motorway drive @ 65mph and mark the spot

 

ya should do if ya get a higher reading in future you go a problem  

[carbon]

Mine normally sits at 'N' and I would be fairly relaxed about it going up to your 'yellow' line in heavy traffic (long queues) as it has a 82C thermostat fitted. Anything over yellow in traffic and the heater would be getting switched to max.

 

It has never gone above 'N' when on motorway or similar fast road, if it did then I would be backing off the loud pedal.

[minimans]

Trouble is it's a guess anyway, If you got a laser thermometer and actually checked the engine temp at various stages then you'd have a better idea of whats hot and whats not.............. Or just replace it with a Smith's capillary gauge?

[cal844]

My 998 saloon(RHD offset guages) sits on the half mark, then upto 3/4 gauge in traffic

1275 sits at 1/4 guage, it never moves haha

The Estate is up at the start of the red, maybe 1/2 inch from the top of the guage when up to temperature

[carbon]

Trouble is it's a guess anyway, If you got a laser thermometer and actually checked the engine temp at various stages then you'd have a better idea of whats hot and whats not.............. Or just replace it with a Smith's capillary gauge?

Maybe that's why it is called a gauge and not a thermometer? You could call the capillary gauge a thermometer as it does give you an accurate temperature reading - as long as it's in the coolant...

 

A temp gauge heading from it's normal 'N' into the red is a sign of potential trouble. But should it go suddenly from 'N' down towards 'C' then that's also a real cause for concern. It could mean that you have lost your coolant through a leak, and the sensor is not in contact with the coolant. In the worst case you keep on driving and potentially end up with a red hot siezed engine a few miles down the road.

 

Or sudden drop from 'N' to 'C' might just meant that the wire has just dropped off the sensor (I had this happen a couple of months back, pulled up smartish to find the push-on brass tag on the sensor had fractured).

 

The standard gauge is a useful indicator, I would be nervous driving a classic mini without one.

[russo]

Trouble is it's a guess anyway, If you got a laser thermometer and actually checked the engine temp at various stages then you'd have a better idea of whats hot and whats not.............. Or just replace it with a Smith's capillary gauge?

Yip, I agree with minimans, never trust an electric guage, check it with a thermometer to make sure it is reading correctly, it not then fit a capillary type.

[Zach P-D]

My gauge on my 1275 would get to half and sit there, no matter what i did, only in traffic would it creep up slightly, but soon stop just above the line.

[Ethel]

As said it's only an indication. The needle will rise steadily until the thermostat opening temperature is reached, ideally it will then stay put, make a note of that position. The gauge can go higher if the engine is working harder, such as going up a long hill, without giving being a concern as long as it returns to the noted point within a few minutes. If it takes forever to reach the mark, or is constantly fluctuating, it suggests the thermostat won't close.

 

If the engine gets too hot the water will boil and the pressure cap will blow. You might see steam from under the bonnet, but the temperature gauge is likely to read lower as evaporating water takes more heat and the water level can drop below the sensor. The gauge can also read low if a slight leak drops the water level or failed pressure cap allows evaporative cooling, if the heater also starts blowing cool it's a strong indicator the engine isn't being cooled. It's definitely time to stop if that happens or the engine starts stuttering or pinking.