Using a 4 stroke mercury outboard compression chart
If you're trying to figure out if your engine is still healthy, looking at a 4 stroke mercury outboard compression chart is usually the best place to start. It's one of those things every boat owner eventually searches for, usually right after the motor starts acting a bit sluggish or sounds "off" while idling at the dock. Compression is basically the heartbeat of your outboard. If it's strong, you're probably in good shape. If it's weak or uneven, you're likely looking at some weekend-ruining repairs. ...