Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing High temperature

On the motorway last weekend on a hot sunny day (over 25C) the temperature gauge was around 90 but towards the end of the trip with a bit of town driving it was showing 100. What should the reading be on a hot day on a motorway run? I thought the airflow to the radiator at around 65 / 70 mph should be good.

The gauges are very similar in action to the fuel one in that they can be anywhere.
My Plus8 runs at 90 but indicates 80 and the fan cuts in at an indicated 100 but this only happens in crawling or static traffic. Unless your fan cuts in when you are moving at speed I wouldn't be overly concerned it could well be the gauge calibration.

Thanks for the advice Richard. That's reassuring. This may be a stupid question but how would I know the fan is cutting in?

Tom, if you are in traffic you can normally hear it and you get an indication via the battery voltage lowering as these fans are powerful. Mine is a single high speed one, from memory of my Sport the newer cars have a 2 stage one triggered at different temperatures obviously starting medium speed and progressing to high if needed ECU controlled I believe.

At motorway speed you would be lucky to notice any indication it was running I would say.

A good way of forcing the fan to run is when you get back off a run just let it idle for a while and it'll kick in and you will get a handle on the sound.

Thanks for the explanation. I had visions of my wife having to climb out on the front wings and opening the bonnet at 65mph to take a look! I may underestimate the technical issues but I would have thought that getting gauges to be accurate would be achievable for Morgans.

That's brightened my day up already.

+1. My car runs normally at an indicated 80. The fan kicks in at 90 but last year driving the Motorways of S Italy with 30 plus ambient it went up to 100.

If you buy an ODBII dongle on e bay plus the torque app you can also get a read out of the temperature from the ECU.

My last Mog was a 2016 +4 gdi, the temperature gauge was always about 100 in warm temperatures, the fan used to cut in regularily, none of my other Morgans did this, I presumed the style of engine just ran hotter. Anyone else with a +4 gdi find theirs running hot?

"On the motorway last weekend on a hot sunny day (over 25C) the temperature gauge was around 90 but towards the end of the trip with a bit of town driving it was showing 100. What should the reading be on a hot day on a motorway run? I thought the airflow to the radiator at around 65 / 70 mph should be good."

This sounds about normal to me. My 2014 GDI Plus 4 did run hotter when it was new and I guess the engine was a bit tight but it dropped back a little later. It may be worth replacing the rad with an alloy one if you considering any touring in southern Europe. They are more robust than the standard fit item, have a larger capacity, better cooling and they look better so it's a win win.

Thanks everyone for your input. Very informative! I like the idea of an OBD reader as well as I really need to get educated about modern vehicle electronics. I'll look into the alloy rads as well but I assume that would void the warranty on the car so best done later?