It never ends! (by alaric)
Indeed, it gets worse.
Remember we're borrowing Sarah's parent's car because ours' brakes failed?
Well, it keeps running hot - the coolant temperature gauge was getting alarmingly high when driving in town traffic. So before going out today I tried to find the bonnet release to check the water level. We don't have the car's manual, or a Haynes manual for it, so we had to search about as best we could, to no avail. We rang Sarah's parents, but just left a message on the answerphone, so we went out shopping. As long as I took routes that maximised time on dual carriageways so the speed kept up, the temperature would be fine. At that point, I was suspecting the cooling fan may be at fault.
However, the car started to make nasty grinding sounds when I dropped into neutral at traffic lights (it's an automatic). So we pulled over, and rang Sarah's parents again; this time we got through, and they explained where the bonnet release was (it was where I'd first looked for it - but a bit tucked away!). Popping that open, I found that it was quite low on transmission fluid, but it was too hot to check the water level; the tank was too opaque to see the level without opening it, which would be dangerous without waiting for the engine to cool down.
So we went off walking to find a petrol station to buy more transmission fluid, and some water in case the water level was low when we came back and opened it. The first petrol station we came to had one of those little Tescos on it, which was useless - it had aisles and aisles of food, and a few shelves of very basic car supplies; engine oil and lightbulbs.
So we journeyed on to a 'proper' petrol station which had a tiny shop, a good eighth of which was full of useful car stuff, including automatic transmission fluid. I picked that up, plus three litres of water, since Sarah was hot and thirsty.
Back to the car. Put 200ml of transmission fluid in, opened the water, and found the expansion tank totally empty.
Doh.
In goes just over a litre of water, and it was up to the MAX level. So we drive on. The car now doesn't make any nasty noises when going into neutral, and seems to be running a bit better in general.
With all these delays, we're now having to rush straight to the nursery to pick Jean up; but on the way, the temperature gauge keeps creeping up again, and when we have to go into the little 30mph roads towards the end, it approaches the red warning section and a steamy hissing whistle emerges from under the bonnet. We pull up at the nursery, picking Jean up just as the staff are starting to go home, and sit and wait while the engine cools down enough to open the water expansion tank again.
When I check, I find it empty once more. I suspect that it may have been REALLY low on water; when I filled it up before, there was lots of bubbling as air worked its way up through the system and came forth, so perhaps the litre I put in was only filling the expansion tank because of trapped air, and running the engine had cycled it around. So I fill it up again, run the engine a bit (you have to do this to check the transmission fluid level, which I do), and the water's still there. I check underneath the car to make sure it's not leaked out.
And so we drive on. But the car's not happy. The transmission is a little odd, with the car 'twitching' every now and then, or shifting down a gear for half a second every now and then. And the temperature still rises alarmingly. So we pull over into a pub near our house, and leave it cooling down while Sarah runs to the toilet (she'd been holding it in for a while now) and we have some dinner; since not having been home between shopping and picking Jean up, we've not been able to get dinner started.
So after a while I go out again, and lo and behold, the expansion tank is again empty. I top it up again, but this time I'm rewarded with a wet trickling sound, and the water level in the tank goes down before my eyes. At the same time, a puddle emerges from beneath the car.
Bugger.
Further peering down inside reveals that I can see water running down the back of the engine, although its source is hidden in shadow and obscured by engine parts. It might be a hose (easily fixed), a "core plug" that protects the engine from coolant overpressure or freezing by popping out to release the pressure (easily fixed) or a crack in the engine block (written off car). Either way, it may be hard to diagnose without lifting the engine out, since the leak seems to be on the back of the engine.
We carefully drive it home, downhill all the way keeping the revs as low as I can. Tommorrow, Sarah's parents come up in our van, ostensibly to drive home in their car and leave the van with us. But there's no way their car's going to be ready to drive all the way back to Essex unless we fix it over the weekend. And if Sarah's parents go home in our van because their car is dead - we'll have trouble getting Jean to and from nursery...