> What could be the cause of this overheating?
Harvey, there are lots of reasons these cars overheat ... basically, the cooling
system was barely adequate even when new, so everything must be in more-or-less
perfect condition to keep it cool now. There isn't any margin for error, so to
My 59 TR3A had very similar symptoms to yours, and I went through everything :
dragging brakes, ignition timing, mixture, valve timing, clogged radiator,
clogged water jacket, stuck thermostat, slipping fan belt, bad water pump, blown
head gasket, etc. I already had an electric fan; but this problem was at speed,
it was fine just idling.
Finally I went back to the shop that had rodded the radiator for me, and asked
them for help. They ran an efficiency test on the radiator, and found that the
tubes were not in good contact with the fins ... it wouldn't conduct heat from
the water to the air. They recored it with a modern core (and no crank hole)
... the problem vanished !
Might not be your problem; work through the list above first. But it's
something to keep in mind.
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