Agree with LoosBenz. Full temp drop (from 227 to ambient) would indicate a coolant flow problem. Minimal temp drop indicates an AIR flow problem. You need more air. Does the car still have any noise panels underneath? How many amps are your fans?

Remember that the AC condenser is warming the "ambient" air consumed by the radiator from 10-40 dF, depending on all the variables. Stick a thermocouple betwixt the condenser and radiator, then at the radiator outlet.

The monovalve should always be open/flowing and have 12 VDC on one side (if the fuse and wiring are good). The climate head supplies a GROUND to make the valve cycle/engage and block coolant flow. Polish wiring on a Kraut car; common political border? The 126 mono is a weird one that tees to allow the snow-melt windshield heater to function.

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James Marriott
2003 Buick Regal
1983 300D (228k, frau Auto)
1996 Suburban K2500 (192k, 6.5 turbo diesel/4WD towmaster 10,000)
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1987 300SDL junker 170k
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