Overheating? Help!

[Limeycat]

Have just come into possession of a K-reg Toyota Corolla diesel, which I'm supposed to be selling on behalf of my parents. 

Having done a 50 mile motorway journey this morning, I arrived home to find there was a trail of water (?) behind me, a growing puddle under the car, and steam gently rising from under the bonnet.

I'm assuming this is something to do with the radiator, but can anyone suggest how I can resolve it without an expensive trip to a garage?

Cheers

[Impret-Sir]

Its more likely to be a split hose than the rad itself. Fill it up with water, (WAIT UNTIL IT HAS COOLED BEFORE REMOVING THE RADIATOR CAP!) run it until the engine is hot again, then have a good visual inspection, particularly around all the water hoses, give them a squeeze and check for splits/leakes. As the system is under pressure any leaks should be easy to find. Replacing a split hose is an easy DIY job. If it IS the rad, this is not really that difficult a job to replace, but it is more fiddly, and, of course, a new radiator will cost a fair bit more than a hose!

[Limeycat]

thanks very much - I'll give it a go!

[jake-the-peg]

It could also be the water pump failed

[Limeycat]

Hmmm... have just followed Impret_Sir's suggestions... bit inconclusive:

Radiator took just over half a litre of water to fill; ran the engine for a few mins - no visible signs of splits or leaks on hoses, although still what seems like water dripping (definitely not oil) - it looks as though it's coming from further back than the rad, although I suppose it could be running back and dripping from the lowest point!  The temp gauge went up to about half way, but didn't keep rising when I revved the engine.  There is a horrible tapping sound (it's a diesel - I believe they're noisier than petrol); this noise is worst when the engine is idling, seems to lessen when the engine is racing.  Could this be related?  Any further suggestions much appreciated...

[jake-the-peg]

You'll have to get it hot and find where it's coming from.

Take it for a drive for five or ten minutes and check again.

Keep an eye on the temperature guage if it gets hot nd suddenly drops to normal or below that could indicate you've no longer got any water going past the sensor.

Don't overdo it though driving an overheated car for any distance is a good way to mess up the engine - check you've plenty of oil too because if it does start to overheat the oil will be doing more than it's share of the cooling.

The noise you're referring to sounds pretty much what I'd expect on a K reg diesel