2001 Mercury Mariner 50-60HP Factory Service Manual, Page 51Get this manual
GENERAL INFORMATION
Cylinder Leakage Testing
NOTE: Cylinder leakage testing, along with compression testing, can help the mechanic pinpoint the source of mechanical failure by gauging the amount of leakage in an engine cylinderRefer to the manufactures tester instructions for proper testing procedures
Courtesy of Snap-On-Tools
Cylinder Leakage Tester (Snap-On-Tools MT324)