3Bean is Hot! (Cooling issues)

[altiain]

Are you sure the stock cap is 12psi? I seem to recall it saying 1.1 bar, which is ~16psi (actually 16.17psi to be precise).

[POS Racing]

From the Mazda Service Manual for us Vintage Miata owners, you new kids may have a different cap.

INSPECTION
Radiator Cap Valve
1. Remove foreign material (such as water residue) from between
the radiator cap valve and the valve seat.
2. Attach the radiator cap to a radiator cap tester (commercially
available) with the SST. Apply pressure gradually to
73.6-1 02 kPa (0.75-1.05 kgf/cm2, 10.7-1 4.9 psi ) .
3. Wait about 10 seconds. Verify that the pressure has not
decreased.

Auto-Zones normally have the pressure tester available for free rental.