Test that cap again, new doesn't mean good. Make sure it can hold the correct pressure. If you think you have radiator blockage, you might find it using an I/R thermometer. Is the radiator in good shape (fins, tubes damaged or rotted)? Is everything else in good condition? (water pump, ALL hoses, fan/clutch/shroud, correct t-stat). Test the coolant for hydrocarbon traces if you think the block or HG is at fault.
|