Try the cap first as indicated.

If there is a coolant leak, the hose should not collapse as air replaces the missing coolant.

If you remove the cap, does the hose expand back to normal?

The hose collapses because the pressure inside the cooling system is less than the atmospheric pressure. On a cold engine, the internal and atmospheric pressures should be about equal.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

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