I've said I'll have a look at my friends 1.2 8v Punto 2. She's having an overheat issue that only presents after quite a long trip and a stop. For example, she was driving us down to Newquay for a week surfing (ironically she insisted on driving because she thought my 147 would break down!). We'd covered about 85 miles without issue, stopped off at the services and within 3 miles of leaving again we'd overheated and we're on the hard shoulder. Rad tank was boiling over. Garage in Newquay put it down to a dodgy fan, replaced it, and then she's had the same issue again.

Any common faults on the cooling circuit worth checking? My thinking is air lock, dodgy stat or blocked hose?

Also, where are the bleed screws on a 1.2 cooling circuit?

The Punto will keep itself cool with forward motion. When you slow or stop the fan is supposed to kick in. Because it happens so infrequently anyway many never notice that it isn't working until the overtemp lamp comes on.
Start the car and carefully disconnect the temperature sensor. The fan should come within ten seconds. If not something is wrong. This thread is typical of how to set about fixing it.
https://www.fiatforum.com/punto-ii/428001-losing-oil.html

The primary bleed screw is a plastic wheel on one of the heater hoses at the rhs of the motor. The other one is on the top of the radiator, usually the rhs but a Y car may have it on the left side.

if you are gonna keep overheating, head gasket is gonna pop if it isnt already
first look if you got enough antifreeze inside, then i would get mes and cables or bluetooth adapter and try to run rad fan from there

few bleeding techniques and bleed locations

https://www.fiatforum.com/punto-mk2-2b-guides/347158-coolant-renewal.html
https://www.fiatforum.com/punto-mk2-2b-guides/348260-thermostat-change.html
https://www.fiatforum.com/punto-mk1-guides/43906-bleeding-cooling-system-8v-16v-petrol-engines.html
https://www.fiatforum.com/punto-mk1-guides/90237-bleeding-cooling-system-mk1-punto.html

Thanks guys. I have a Bluetooth OBD adaptor and MultiECUScan so I'll give that a go. Also have the cable for my 147 so hopefully that'll do. The garage in Newquay charged her £60 to fit a new fan, hope she's not been had.

Turns out her head gasket is on it's way out. She's losing oil and the filler cap had a very thick layer of emulsion in it; that's new as it wasn't there a month ago (I checked!)

not necessarily, mayoneze below oil cap could alse be due to short trips

If it was my car then I'd go for that, but the shortest trip she does is about 15 miles; anywhere less and she rides her bike!

it could be a duff thermostat - sticking in all the wrong places

It could be lack of coolant movement due to an airlock OR water pump

It could be a poor conductive radiator - rad weld, or lots of rust water clogging it up

Who know's!

Mayo oil cap isn't a definitive answer to is it HG?
Only when you notice other symptoms that match a HG been blown then i'd worry

For example, your lovely red coolant is now suddenly a dark shade of black
A continuos air lock that could never be cured

All happened after a 300mile trip, without a SINGLE overheat....
The car was happy all the way

Ziggy

Check that the fan is operating as designed. It should come on after 15 mins at idle. If you don't want to wait that long you can disconnect the temperature sensor when it's running and the fan should be on about ten seconds later. The eml will remain lit for the next three cycles and then go away.
What is happening to the coolant level ? The vast majority of hg failures will have coolant loss.
Typical early signs are coolant loss, slight misfire when cold, slight white 'smoke' when cold, gurgling in the heater matrix at start up caused by coolant loss, one or more spark plugs steam cleaned.
A compression test is fairly conclusive.
There is a shedload of stuff on here about fixing the headgasket which is relatively easy on the 8V.

spark plugs steam cleaned

is that black color deposits?