Hey please help. I’m thinking about buying  a 1994 Bass America 1648

It has a 40 HP on it 

Can I add a 9.9HP kicker on it for local hp restricted lakes??

What is required to do this… just enough room to clamp it on and go? 
I can’t figure how to add an image but if you just google it you can find one. 

Any help is very much appreciated !!! 

Depends on the weight rating of the boat/transom. The weight rating will be on the hull ID tag. What are you going to do for fuel? If you add a separate tank, that adds another 50lbs, plus 90-100lbs for the motor. That boat might be ass heavy.

Ya - considering that's a decked jon-boat - if you want to run on HP restricted lakes, I'd be more inclined to swap motors...two motors on that thing and it's gonna be butt-heavy if the transom could even take it.

Also the kicker is probably propped for trolling for slow speeds . I agree to just swap motors 

What hp is the boat rated for, if your already at max then probably to much weight.  Are you looking at a four stroke or two stroke...big weight difference...is your current 40 hp a 2 or a 4 stroke ??  Lots of things to consider here.

Had your style of boat with a 9.9 kicker on it only for that purpose, hp restricted lakes. Boy did that suck. I think i could get out and walk the shoreline faster than that thing at 100% throttle. Definitely do not get a kicker.

 

Unless your current 40hp (even if it is a 2 stroke) doesn't weight that much, removing it and putting on a 9.9 is the way go to. However since I couldn't lift off a 40hp 4 stroke by myself, I wound up going to harbor freight and installing a cheap $60 winch (+$10 for bolts) on my garage ceiling. I also bought a $20 Mercury Lifting Eye for the motors. I built a motor stand outta 2x4s for almost nothing to keep the motors on. Made swapping the motors super, super easy and comfortable.

 

Nobody wants to ruin a possible weekend throwing your back out or possibly dropping your motor.

 

OH, here is your DO NOT DO THIS, horrible bad life pro tip to fix your issue. Just get a sticker and hope nobody notices:

 

 

If your boat can handle the 9.9, you will be fine...the question is IF it will handle it on top of the 40 hp.  I have a 16' aluminum side console with a 40 hp Merc 

( boat is rated for 80 hp) and I have a 2.2 hp kicker and it works!!  Use it with my bow mount electric for trolling....the 2.2 is locked straight ahead and the bow mount is for steering from the remote control...works great !!!  What is the boats max rated HP ??

The 9.9 hp Merc is the same engine as the 15 hp and easy to convert. Go online several articles and videos detailing the carburetor, shim, and idle jet part numbers.

Tom