If bleeding relieved the brake pressure = the most likely issue is brake flex hoses collapsed internally = acting as one way valves = replace all four hoses.

The ting should have been metal cooling.
When the brake fluid temperature rises to high = it flashes to vapor in the caliper = no brakes = allow it to cool for an hour and retest the brake pedal.

From your description = the brake fluid must be flushed = the fluid is toasted, which causes acid formation.



Have a great day.

__________________
ASE Master Mechanic

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1985 300SD
1983 300D

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