Oh font of knowledge, I think I’m going mad.

Ford focus, 2L petrol

has been overheating for the last week to ten days

water and oil levels ok
Fan is kicking in no problem

intermittent at first, going up under load, then dropping a bit when downhill – actually seemed to drop as the revs increased too (?) – at that point, hot air blew through the vents ok

but last two journeys constantly climbing over a little over five miles to the point of engine light coming on, and no hot air through the vents if I try them, and the water reservoir was full to the top with hot water

have run the dashboard diagnostic and seen it climbing on both cylinder head temp (got to 124, then light comes on) and coolant temp (was reading 139 degrees!).

booked it into garage, thinking its probably water pump – they have pressure tested system and its ok, but they cannot replicate the overheat – they put it running on tickover this afternoon, and its sitting in the middle of the temp, and the fans are kicking in.

could there be anything I’ve missed – my understanding is that if theres no heat through the air vents on a hot engine, then its almost definitely the water pump.

any ideas?

cheers.

Blockage in the radiator?

Is the rad getting hot?

be honest and say I’m not sure if radiator getting hot, (sorry, still at garage so can’t test) but the big squeezy pipe at the back of the radiator is full of hot water – and the hot water that fills the reservoir seems to bubble out the two small pipes at the front top of the reservoir.

the water in the reservoir, full when hot, seems to settle back into normal level once it cools down

Hmm, water pump sounds most likely.

Sticking thermostat combined with water pump maybe.

I was under impression that it couldn’t be thermostat, as the fans are kicking in.

for reference, its on about 113k miles, and the book says timing belt was done at 90k (but no mention of the water pump being done then)

cheers for the help so far.

Thermostat will open to allow rad to cool the water, the fans only come in later if the rad can’t control the temperature. Short term solution is to drive with the heater on full blast as this gives extra cooling effect.

Depending on engine, not all focus engines are cam belt driven water pumps. It’s not a bad job to do, seen a few golfs lately where the pump impellor has come away from the shaft, so spinning freely, over heats etc.