Oh, yea.

I'd go one step farther----take a propane torch and light it----go test
the system for leaks !!!

I would first call you local undertaker, prior to doing either one of
these testing methods.

Soap and water is the safest, unless you have a electronic leak detector
laying around.

Use a lighter-----My God, where do these nut cases come from?

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Terry
74 Campmobile (Clementine)
85 GL
86 BMW 325 ES