Long Shaft Motor on Short Shaft Transom

What concerns should a person have running a long shaft motor (20″) on a short shaft transom (15″).

We’re talking a 25hp on a 16ft aluminum boat.

Pete

Pete,

I would advise you to drop the boat and motor off at my house and only use it on the red cedar in spring

Sorry I couldn’t resist.

Pete,you could use some metal angle 1 1/2″ X 1 1/2″ bars and cut them long enough to bolt on your transom and raise your motor up the 5 inches.I have an alumacraft V-16 that I unbolted the wood transom and epoxied 2 pieces of 3/4″ plywood and cut in out 5″ taller,this worked out perfect.This 2nd method is stronger and looks better.Pete just make sure you keep the anti-cavitation plate about even with the bottom of the hull,sometimes you get better deals on motors with longer shafts.I’d never shy away from this setup,it’s been working great for me,until a friend made me a nice offer on the 40 yamaha now it’s back to the 30 mariner. Stan

Hey Pete. You really should lift it as your motor is most happy with the cav plate being as close to the bottom of the boat as possible. You run into drag problems otherwise that really will degrade the performance of the motor. If the boat is light, you may have the bow really kicking up when accelerating and unpredictable performance when turning.

On my last boat I had an 1/2inch piece of aluminum bolted to the outside of the transom. Then used treaded wood to cover the thickness of the transom.

DT

I think it was Bass Pro Shop that I saw a mini jack plate made just for that

Would something like this work?

http://www.iboats.com/Auxiliary-Static-Transom-Motor-Mount-Plate-Panther/dm/view_id.164148

Russ – I’ll be over on the Red Cedar