Definition of quantal. 1  1 [Latin quanti how many, plural of quantus] : of, relating to, or having only two experimental alternatives (such as dead or alive, all or none) 2  2 [quantum] : of or relating to a quantum.
3. Engine movement. Another symptom of bad or failing engine mounts is an engine that moves in the engine bay. If the engine mounts are in good condition, they should be able to secure the engine firmly in the engine bay.
A typical O-ring failure is caused when the engine overheats., warping the alternating layers of aluminum and steel in the engine sandwich relative to each other. This small separation exposes the fragile O- ring to direct pressure and heat from combustion (on one side), and to coolant pressure on the other side.