diesel knock what is it ?

[royfiona]

hi all ,have fitted a 1.9d to my high top t25 engine starts great revs smooth turns off crisp but there is a knock or a deep sound bang, neighbour said it`s diesel knock but diden`t know what it was so can any body will it hurt the engine or is it ok
cheers

[Cableguy]

Maybe record it and post on you tube, post the link on here

[footstuck]

Hi mate
Because the injected diesel has to reach burn temperature before it will go bang, injection commences before the piston has reached the top of its stroke. This is because the compressed air looses its temp as the piston goes over TDC and starts to descend (unless the burn has been established).
Getting the perfect point of injection is done in the design stage, and that is what the timing marks are for.
If there is no carbon or other matter in the combustion chamber or on the piston crown and the correct head gasket is fitted , the only other things that I can sugest may produce excessive diesel knock are advanced timing, bad fuel, or extremly low engine speed.
Hope its an easy fix mate