How knocking in the engine cylinder may be explained?
27 Jun '17, 05:58
Knocking may appear mainly because of two factors:
1) Excessive fuel supply during the combustion stroke. Excessive fuel in the combustion chamber may be due to ignition delay and cause a sudden increase in the pressure. This excessive pressure will cause an excessive knocking effect in the engine.
2) Excessive wear clearance and failure of the main bearing, crankpin bearing or piston pin/bush.
To find out where the knocking in the cylinder caused by fuel oil or wear cutting off the fuel oil for the cylinder and check if the knock persists or not. If the knock persists after cutting the fuel oil there is some excessive clearance in some of the running parts. Often it is badly worn piston pin and bush. Hence every time when the piston is changing its direction from upwards to downwards it will give the knocking effect. Inspect the piston and crank pin bearing at the earliest opportunity.
27 Jun '17, 06:07