amp meter
You are most likely correct...the meter is too large for a small sailboat with a outboard. Most likely a 0-20 volt, voltage meter would be better and more helpful. The original intent of a 50 amp meter is to show battery charging from an alternator, or shore power and battery drain. However, the scale is too large, 0-20 amps would be more appropriate to your needs.That's why the meter doesn't move.