hi guys i have been handed this engine to find out if there is a problem with it.it seems to be very low on compression, i have had the guts out of it and it seems to have had a new liner and piston and a new ring fitted. the only thing i can see that may be caurseing a problem is the ring may be getting pinched by the ring grove in the piston which is not letting the ring expand to fit the liner bore would i be right in my thoughts???or could it be the liner collar that has been machined to long there by increaseing the conbustion chamber and there by lowering the compression i am totally stumped by this 1 can any 1 help please