Back compression is the resistance of the engine to turn over during starting due to high pressure in the combustion chamber.

• Occurs when the engine is turned off with the throttle open, causing fuel a...read more

Piston Ring weak that is engine back  compression 

When piston ring is worn out and and cylinder head gasket is worn out causes back compression . Reason due to overheating or no timely service done 

checking of piston and connecting rod   is not breaked or leaked