General When to panic re: overheating

[msT]

We recently had work done on the car including a new fan. It's on 3 bars most of the time but in traffic or waiting at petrol station it goes up to 4.
Today I got a bit worried as I did a motorway for the first time, M25 was at a standstill, I managed to pull off at an earlier junction than I intended but if I wasn't able to what should I have done? I did turn the heating on full blast and melted a bit.
How many bars do you get to before you really worry and turn it off?

 

[Shepherd]

For the past 5 years my JTD has run at 4 bars after about 10 minutes of running which I think is ok. Last winter which was very cold it took quite a bit longer to reach 4 bars and hovered around 3 for a while. Even 5 bars may be ok but anything over that I would imagine would be too hot, but I would hope the Multi has a built in alarm if it got to this??

 

[Zundapp]

It's a bit obvious I suppose, but have you checked to make sure the fan does actually cut in?

 

[joipalli]

On my petrol I sometimes see the fifth bar, and can hear the fan running. Yes there is a warning light for overheating.

From my manual:

Note: Don't stop the engine, pull over and let it idle faster for 2-3 minutes!

 

[MultiPa]

We recently had work done on the car including a new fan. It's on 3 bars most of the time but in traffic or waiting at petrol station it goes up to 4.
Today I got a bit worried as I did a motorway for the first time, M25 was at a standstill, I managed to pull off at an earlier junction than I intended but if I wasn't able to what should I have done? I did turn the heating on full blast and melted a bit.
How many bars do you get to before you really worry and turn it off?

Mine runs on three bars with the occasional fourth bar in heavy traffic or after lots of starts from rest in succession.

It has got to five bars once so far, on a very hot day in the interminable queue at the end of the M67, which is a slight hill. I put the heater on too, and found that if you set it to face only, close the centre vents and open the windows, you can just jet the hot air straight out - I didn't feel any hotter for it. When I did that it dropped to four bars fairly quickly, and settled down to three not long after we got out of the queue.

Incidentally I noticed that it took quite a long time for the hot air to get through to the vents - there must be quite a long path it takes?

 

[matt8772]

four bars is fine, the three ive had have always run between 3 or 4 bars.

any higher than that and id be getting out and checking my coolant though!

 

[matt8772]

mines a jtd btw, so will run a bit cooler than a petrol.

 

[MultiPa]

Mine is also a JTD, but I assume Fiat will have calibrated the dashboards so the temp display is similar? Maybe not!

 

[MultiPa]

Got stuck in the same traffic jam as earlier int he thread on Friday and it went up to 5 bars again, but it wasn't that hot a day, so I did the air vent out the window thing again and it was fine.

It occured to me though that I couldn't hear the fan, and sure enough on looking at it today, the conectotors weren't plugged in correctly - I still can't hear it, but whereas before it used to get to 4 bars when warming up and then drop to 3, it didn't go above 3 today, so presumably the fan is now working