UK Car Repair: Vauxhall senator overheating, vauxhall senator, coolant level

Question
Hi Many thanks for your helpful response. The engine seems to start labouring and not picking up as normal as if the engine is seizing up would a fault with the thermostat do this ? The coolant level and oil level are ok but it is as if the oil is not flowing. If it were say the oil pump would this be reparable without taking the engine apart. Again many thanks your advice is much appreciated. Best wishes Nicholas
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Hi, The car starts and after about 3 minutes the temperature gauge starts to go up and the car gradually slows down and when you stop it stalls. When it has cooled down it starts ok but the same thing happens. Any help with this would be much appreciated. Best wishes Nicholas
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Is it actually overheating, or is it an electrical problem? I'm assuming you have checked the coolant level, odd gauge readings often occur when the radiator is very low. The next step would be to check that the thermostat is operating.

Answer
Hello Again, A blocked thermostat would cause a very quick rise in temperature. A hot engine tightens up, but usually it is an extreme reaction.   You mention oil circulation, is the gauge or light operating?  Any engine that has been run with no oil circulation will very quickly self destruct, it will also be very noisy. Look inside the oil filler, there should be evidence of fresh oil. When the engine stops does it feel very hot and can it be turned over with the starter?