My MGB has a problem in traffic. When it’s stop-and-go, the temperature gauge creeps up. Sometimes I’ll have to turn the heater and blower on – in Summer – to keep it from overheating. After a time, the engine will start running rough and then it stalls. I’d assumed it was the ignition coil or the electronic ignition module balking in the heat.
I wonder now, if I’m experiencing vapour lock. Though it has an electric fuel pump situated in the right-rear wheel well, the carburettors are right above the exhaust manifold.