Motor size for modded 14 ft jon boat

I have a 9.9 on my 14ft jon boat now but I need something a little faster. I added a wood deck to the front, wood flooring, 12v battery in the back and gear so there is added weight. The boat is an extra wide extra deep jon boat. What's the biggest motor you would put on it?

What does the plate say? Is there one on the boat?

I'm running a 25hp Mariner built by Yamaha on my 1436 jon. The motor weighs 105 pounds and is mounted on a mini jacker.

My 2015 Tracker Topper 1436 is rated for 15hp also tag shows maximum weight 345lbs. for 3 passengers.

Jim said:

What does the plate say? Is there one on the boat?

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There is not a plate on the boat. Its an older boat that I bought off of a farmer. No telling when that plate came off.

By the USCG's sizing calculation a flat bottomed 1436 with a 15" transom will be rated for no more than 15hp. These boats are designed to be lightweight. Add all that lumber and you defeat the P.O.U. of a small aluminum boat.

You can use www.NADAguides.com and look up outboard motors to search around and find the lightest motor for the size you're looking for. In the 20-25hp range you're looking @ 100-105 lbs for either a Mercury/Mariner, Yamaha or Tohatsu, but an evinrude will run ~120lbs. Consider you've probably got 200lbs of decking in there already plus your weight & your gear...all adds up fast in a small boat.

ALL 1436 jons are not created equal guys. check out Lowe's website . They have a model 1436 rated for 20 hp and a model 1436L rated for 15 hp. The difference is the gauge aluminum they are built from.

Power rating is strictly based on length, width, height & bottom chine. That being said you're right, Lowe does have a 1436 rated for 20hp which is really cool - but to get that rating they must have added a smidge to one measurement or another to get it over the minimum calc. to be rated @ 20hp.

My buddy has a 1448 Lowe with a 50 Johnson, but it has a remote steering console.

I am sure a 40 tiller would make you happy.

a side console layout would change the chart that the HP rating would be determined from - but depending on the boat layout the only variables from there are those i mentioned.

Depending on the 9.9 you can up the horsepower to a 15hp. Involves parts and work.
We see a lot of heavier 14s down here with 25s on them. Seems to be a good combination when you add a bunch of weight to them.

1448 alumacraft with a johnson 40hp. and i love it. i can load it down with camping gear and it doesnt skip a beat!

War Eagle's 1436 is also rated for 20 hp. Lot of them run 25's.

Something worth mentioning...if you want to stay within the "rule". Pick up a 20hp Yamaha, the old 2 stroke version. Replace the carbs with a set of carbs from a 25. Then you have a 25hp motor. Same exact engine, same exhaust (to my knowledge). That or find you a 25hp 2 stroke, peel the stickers and put 20 hp stickers on it. Lot of duck hunters out here will pick up a 30hp or 40hp and put 25 stickers on it to stay legal. BUT....the fish and game guys are getting smart.

Same thing goes for the late '80's Mariners & Mercury 18hp & 20hp XD series motors - just swap the carb for one off the 25hp XD or Marathon series motors & that's the only difference. The motor-side intake is the same. I needed to adjust my timing a little for the bigger carb, but it could have needed it with the 20hp carb as well and I just didn't take a timing gun to it prior to the swap.

I believe Evinrude/Johnson's were scaleable all the way up to 35hp, but you needed both the intake plenum and the carburetor if you went to 30hp or 35hp