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.
If your engine mounts are more than five or six years old, or have been contaminated with seawater, engine oil or coolant, change them. Even if the mounts look perfect, the tough elastomer (rubber-like) material in the engine mount work-hardens over time and ceases to isolate the boat from the engineâs vibrations.