I sprayed some carb cleaner in the chamber and it seemed to work OK. The pluhs all seem to have a grey chalky deposit on them. Maybe the engine is running too hot -- the carbon in the chambers is probably from the age of the car.

DennyW said:

"Have you ever tried the engine warmed up, high idle, water poured through the carb trick? Accel and decelerating?"

Do you literally mean water in the carb? Wouldnt that destroy your car?