A knock probably means a bearing has already gone.
The diesel knock is damaging because it will have a tremendous force on the main bearings and will cause excessive wear of the piston rings.
Rod or main bearings. Those are located on the crankshaft.
Severely over heating the engine may have damaged the main and rod bearings.
No, knocking in an engine is normally more serious than a gasket leak. Depending on how heavy the knock sound is it could be the Big Ends bearings need changing or it if its fainter than that it could be the timing is out. Either way it can cause real damage to the engine and should be repaired as quickly as possible. Have seen exhaust manifold gasket leaks that are described as a 'knock' by inexperienced persons. Normally a knock is piston connecting rod bearings that have gone out.
Depends on the sound of the knock. Could be main bearings or rod bearings.
Worn main bearings sometimes knock when cold starting
Low oil pressure, engine knock / noise.
Normal wear on the bearings inside.
Cam bearings, Main bearings, Rod bearings.
Lack of lubrication, deterioration of lube oil properties, foreign particles and thrust load of the driver may cause the air compressor bearings to go.
Several things can cause a knock. low octane gas worn bearings timing not set correctly or even something loose on the outside of the motor
Lifters can take time to pump up at first when starting....but worn main bearings can knock also