(it normally sits a rock solid 1/2 on the dial once upto temp). I pulled over and discovered that the car was low on water and then when round the front discovered why, a stone has hit the rad and pierced a small hole
(see pic). The leak is minimal (more of a weep), but I guess it could have been leaking for some time hence why the water level has dropped. Having topped up the water level I drove a few miles back to my folks place and noticed that the temp needle shot up
(over a few seconds) and then just as quickly dropped back down to the middle position and stayed there for the rest of the journey. So, my questions are:
1) What would make the water temp needle give such erratic readings? Air in the system?
2) Is it worth seeing if radweld will fill the small hole in the radiator
(based on the fact that I am currently on holiday and need to get the car back home). Any thoughts
/ advice appreciated 
