Have just inherited my fathers '72 4/4. have done the usual housekeeping chores i.e. the wheels are now round, head hardened, carburettor has been rebuilt. I have had the local garage go right through the cooling system and tune the car but it is running hot on the gauge. the mechanic seems to think the gauge is true but has no answer to the problem. needle is well into the H even when cruising and although it's not yet boiled over I am anxious about breaking Dad's bequest and can't yet get any pleasure from the much heralded Morgan experience. Any idea's?