So, when diagnosing a leak, you'd let the system get overpressurized or not start with replacing the weak hoses? That's just asking for trouble, and certainly not the fault of the pressure tester.
A year or so ago I bought a universal cooling system adapter to go onto my pressure tester that mostly only fit USA radiators. The one I bought has served me just fine. I'm not really sure why you'd need to use it with the engine running. If you require a hot test, let the engine warm up with it off, then shut the car down and then use it to pressurize the system. Hold it in place for the 10 seconds it takes to determine if you have a leak. If it takes 2 minutes to find the leak then maybe you need a helper while you check the heater hoses.
This thing will not stay in almost ANY filler neck - it flies out like
>a bullet at less than 10PSI spilling coolant all over the place.
>Also, the pressure release valves (we have had two of these) do not
>work at all. If you leave it plugged to one of a few systems it does
>not fly out on a running engine - as they recommend in order to
>measure actual temp, - the radiator, hose or whatever is weaker will >burst.
>I called them and was told that they "are looking into a possibility
>of new design." They also told me that once - or if - they find the
>solution, it will NOT affect existing owners - defective units will
>not be replaced or updated.
>Leo Russ
>
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