Dreaded overheating problems!!

[boothy]

Hi, I have had my surf for about 6 months with no problems, and on Monday I drove it home from work (about 15 miles) and stopped about 2 miles from home to pick up a takeaway. As I got out I didn’t notice anything untoward. I got my food and drove the last bit home, as I got out on my drive I heard a bubbling sound from the expansion tank and water was pouring out the overflow tube. Not wanting to miss my food, I thought I would leave it until the morning.
The following morning I checked the rad and it was empty, I filled it up and took it out for a spin, in about 4-5 miles it was doing it again. At all times the temp gauge has remained in the middle as normal. I have checked the pipes and they don’t appear to be leaking. I was worried that this was the signs of a head problem and I checked the oil, which was nice and black (could do with a change!) and had no milky residue in it, so I am hoping it is not this.
I have spoken with a diesel fitted I know and he has stated that it could be a failed water pump, and that the water is not being pumped around and it is just boiling in the rad?? Does this sound right? And if so how hard is it to change the pump and roughly how much are they? Any other ideas??
Cheers
Jason

[Linda]

if your heater is blowing warm you can rule out a waterpump, i've really seen a water pump not work that isn't belt related.

may be a stuck stat or weak rad cap, or even a small water leak that has water over months of use.

if its getting hot, 3.0's can suffer from a clogged rad.

only way to rule out a head or head gasket is to get the cooling system tested for exhaust gases, this way you'll know for sure instead of spending frustrating weeks changing this and changing that and not getting anywhere.

[killrag1]

Mine did this. a pressure and chemical test revieled nothing. one of the best suggestions I had was to remove the rad cap and put a condom over the hole where the rad cap goes and seal it with a cable tie or rubber band, block the expansion pipe and run the engine. if the condom doesn't inflate this eliminats the possibility of exhaust gasses forcing the water out.

mine hase stoped doing it now but does loose a little water (1/2 pint a month)