Coolant leak help

You can buy a fitting with 1/8 NPT threads on one end and a schrader (tire psi) threads on the other end for less than $3 at O'reillys. take out the coolant sensor sender & replace it with this fitting then pump it up with your air hose to ~10 PSI or so & see if it holds pressure. as you know leaks can be external or internal. Add air in very short blips cuz it ain't like airing up a tire where you go minuites at a time & you can reach a critical pressure in no time & blow a hose out.

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