What was found
DURING ANNUAL COMPRESSION TEST, CYLINDER WAS FOUND TO HAVE NO COMPRESSION. UPON FURTHER INVESTIGATION AIR WAS FOUND LEAKING FROM THE BACK OF CYLINDER ASSY AT THE POINT WHERE THE FINS STEP UP TO THE NEXT SIZE. WITH AN INSPECTION MIRROR HELD BETWEEN THE BAFFLING AND THE BACK OF THE CYLINDER COULD SEE A CRACK. REMOVED THE CYLINDER FROM THE ENGINE AND WITH FURTHER INVESTIGATION FOUND THAT THIS CRACK STARTED AT THE TOP SPARK PLUG HOLE CONTINUING TOWARDS THE BACK OF THE CYLINDER DOWN AND THROUGH THE EXHAUST VALVE SEAT TO THE REAR EXHAUST MOUNTING STUD. CYLINDER WAS INSTALLED NEW IN FEB 2005.