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  1. 351C Overheats in Traffic/idle. Restrictor Washer

    Classic Cougar Tech
    Can't find a thread to address my specific problem and question. The engine only overheats at idle over a 5-10 minute span. At highway speeds it does not overheat and runs in the normal range (slightly below half). I pulled out the thermostat to check it, and it is a cleveland thermostat...
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