LET MY WAX BALL GO

Theologists have long pondered the puzzle of why God first hardened the Pharaoh's heart only to punish him with locusts, pestilence and death of his firstborn for having such a hard heart.

They may now ponder the puzzle of why EPA ordered Chrysler to recall 886,000 cars and trucks (half of its 1973 production) for having a wax ball in the place where EPA had decreed it should be.

Nitrogen oxides, pollutants arising at high engine temperatures, are partly eliminated by recirculating exhaust gases back into the cylinders. The recirculation valve was, in the Chrysler version, opened by a wax ball which melted at high temperatures, clogging the valve during warm-up. Originally, the wax ball was on the fire wall, where it sensed the heat of the engine and the ambient temperature under the hood.

No, said EPA, the wax ball belongs on the radiator, which gets hotter than the fire wall. Won't work, said Chrysler after it had equiped half of its 1973 models the way EPA had decreed, because after 10,000 miles the radiator builds up thermal insulation and the ball won't melt until the engine temperature is close to maximum. It won't, eh? said Epa. In that case recall all those cars where you obeyed our orders. Will cost you $2 million? Not our department.

EPA's policy has been to get rid of pollution after it is created, not to contribute to technology that will prevent it in the first place. But not even that policy has worked out. Come September, the new automobile models with their catalysts will spew out hydrogen sulfide and sulfuric acid, two toxic pollutants that never came out of car engines until EPA started mothering them.

EPA head R. Train has backed the wrong horse in catalysts, desulfurization of stack gases, ambient air standards and other crucial decisions. He now opposes the administration's proposed amendments of the 1970 Clean Air Act cripple, and the confrontation may come to a head this month. Much will be made of it (any stick is good for beating the President these days), but Mr. Train is flatly contradicted by the scientific evidence, by the National Academy of Sciences, and even by scientists in his own agency.