ISX 450 CM570 taking too long to start and using too much oil

[christiank77]

Hello all. I hope I find you well. I have a problem with my ISX 450 CM570 engine. I have been experiencing difficult starting. It would require more than 30 seconds cranking to start and of late had been consuming excess oil so I decided to get the mechanic to open the engine and check. We found two pistons for cylinders number 3 and 4 looking like picture attached.What could have caused the damage on the piston?Could it be related to the difficult starting?