weather suddenly cold, runs suddenly rough

[Daktari]

My 1965 IIA 109 has been running wonderfully well ever since the temperatures got above 65F last spring. However, the weather in SC turned suddenly cold with temps getting into the 40s at night, and just as suddenly the truck runs very rough from a cold start and takes forever to warm up. Once good and warm, or when the daytime temperature gets up into the mid-60s, it runs just fine. I don't have a long drive anywhere. Any suggestions or advice (particularly from those of you north of the Mason-Dixon)?

[SafeAirOne]

Do you have a good thermostat in it?

No thermmostat or an open thermostat will cause the engine to stay cold.


When I borrowed a friend's 2.25 petrol 109 last autumn, It seemed like you'd have to run it with the choke closed and modulate the gas pedal quite a bit to get it going when the engine was cold. As it warmed up, I could gradually decrease the choke till no choke was required and the engine was up to operating temp.

[Daktari]

Thanks Mark, I'll check the thermostat. Didn't think of that one.