Measure from the top of your transom to the bottom of your keel. If it is from 15″ to 17″ long you’ll need to get an outboard with a “short” shaft. If it is from 20″ to 22″ long you’ll need our “long” shaft outboard. Outboard shafts are measured from the bottom of the engine mounting bracket to the cavitation plate on the lower unit. Generally most boats need either a short or long shaft although some boats require a 25″ shaft (ultra-long shaft) outboard.

Please note that depending on the particular model, some shaft lengths may be 2″ longer than “standard” (ie: a short shaft may be 17″ instead of 15″ and a long shaft may be 22″ instead of 20″). Therefore, depending on the configuration of your keel, the shaft length required by your boat may be different than the above recommendation. Should you have any questions, we recommend that you contact us to determine which is the correct shaft length for your particular boat.