Mityvac MV4560 COOLING SYSTEM TEST KIT - Manual (Page 7)

Form 801625 Page Number - 7
Fig. 5
11. Most leaks are external, and visible seepage occurs.
However, a drop in pressure with no visible leakage can
indicate a blown head gasket or cracked block, where fluid
leaks into the combustion chamber. Visually inspect oil
and transmission fluid for signs of coolant. Proceed to the
Dynamic Pressure Test for better methods of diagnosing
internal leaks.
12. When testing is complete, release the pressure in the sys-
tem by pressing the Pressure Relief Valve located on the
pump hose near the quick-connect coupler (Fig. 5).
13. Repair leaks if necessary, and retest.
14. Disconnect components, clean and store them properly.
15. Refill the radiator or coolant bottle to the proper level, and
replace the cap.