Thanks jezza , firstly I cant drive the car at the mo as it hasnt got any mot , tax or insurance so is just on the drive at the mo . I have to fan on a switch as the sender was broken .I changed the water bottle a few years ago so all should be good. It doesnt appear to be boiling up or anything so I suppose it could be a dodgy reader . I am not getting any hot air out of the heaters inside when i didnt have to matrix pipes bi passed and also the bottom pipe on the rad is not as hot as the rest of them , if that is any help ?
Well, I guess that's your problem. If the car is not moving and the rad stat does not turn the fan on then the engine will overheat. The car relies on forward movement to drive air through the radiator and keep it cool when stuck in traffic or on your drive, it relies on the rad stat to turn the fan on and off to keep the temperature steady, so by switching the fan on and off manually you are doing exactly what the rad stat would do if it was working. You need to replace the thermostat which you have removed or when you do get out on a run the engine will run cool and you'll get crap mpg and poor heaters. The bottom pipe out of the rad should always be cooler than the top as the hot water comes out of the top of the engine and is cooled by the rad, the cooled water comes back out of the bottom of the rad and goes back into the engine via the water pump.
It seems to me that you do not have a problem at all really, just reinstate the thermostat and put in a new rad stat to turn the fan on and off automatically to save you the hassle of manually switching the fan on. As said, the fan should come on automatically at just above halfway on the gauge. Just check that there is no break in the wiring to the rad stat or it may not switch the fan on as its supposed to.
When idling on your drive, once warmed up the fan should turn on and off at fairly regular intervals to keep the engine at a fairly constant temperature. J
