4hp on Intex 3.5hp max motor mount

[matt167]

I'm preparing for a decent day or 2 of cruising a small lake and connected river, as at least one time in the water. So I have a Seahawk 3 with it's 1.5hp max capacity, but it's on their mount which they list as 3.5hp max capacity..

I have 2 outboards to choose from.

A "3.6hp" Hangkai with only it's break in hours on it.. The engine itself runs good, but it uses a Honda Weedeater clutch and an copy of an old Yamaha 2hp leg. It moves water in the barrel, but not sure about 5 miles up river. I literally bought the motor to see how bad they are.. The actual output is around 1.5hp and the unit weigh's 12 lbs.. This is the size motor that the boat should have

Also have a 1997 Evinrude 4. Runs minty, although I put a different carb on it and it will only run from it's internal tank.. Considering this one only because I know it will keep on ticking. It's no heavier than a Johnson 3hp or so being a modded version of that powerhead, but it has a spring gear shift so I could idle it down the river and it's a quiet twin cylinder

 

[GA_Boater]

You are forgetting the motor mount is used on all the Seahawks, Mariners, Challengers and Excurcions, not just the Seahawk 3. The boat horsepower limit is what you go by.

 

[matt167]

I know. Just wanted to use the name brand outboard if it was safe enough.

I have bought several Chinese chainsaws and they are decent copy of older Redmax chainsaws. For the $100 that you can buy them for beats a Poulan every time... The Hangkai while it actually runs and all, does not have the same general build quality that the chainsaws actually have. And it really is a 55cc weedeater based engine stuck onto a 2hp leg, and they cool the exhaust with the water pump so that it pulls some heat off the cylinder head, it's otherwise air cooled

 

[tpenfield]

This is a rubber raft (right?) You want us to tell you that your plan to use a regular 3-4 hp kicker motor on a rubber raft is safe :noidea:

Have someone take some videos for YouTube

 

[matt167]

Seeing if it was possible. But I'll run the Hangkai 1.5hp and just make sure I have good paddles.. It's a glorified pool toy basically. I just want to get on the water with something.

 

[matt167]

What is the best way to affix the hull registration numbers to the boat/ raft on the cheap? I just got it registered since I'm powering it..

I have to affix the state reg stickers as well

 

[Sea Rider]

Install the lightest HP motor available. That $ 95.00 cheap inflatable built with such thin unsupported fabric material will flex even when rowing hard, will blow it up if more air is pumped as to have a more firm inflatable. Throttle the least possible as to avoid

No offense, would not dare using one outside my garden pool, could end in a tragedy worse than the Titanic at open water...

Happy Boating

 

[matt167]

I have the same reservations about it, but since it's the only boat I have that is ready to float, it's really all I have if I want to get out on the water at least once this year... I'm just putting it on a small lake, I forget how many acre but it's not very large... I'll sell it and the Hangkai outboard as a package cheap next year as I won't need either one... I had to watch a number of youtube videos of these under power to convince myself it was even marginally safe

The Hangkai weigh's 12 pounds and it holds 1/2 gallon of gas so it weigh's a lot less than a trolling motor which would have a 20-30 lbs battery plus the motor weight.. I think I will carry 1 gallon of fuel onboard so, 8lbs or so

 

[matt167]

1st trip was a success. Boat didn't rip itself apart although it tried to.. The Intex motor mount drops the motor down just a little too far so the motor tries to drown itself. 1/4 throttle and the boat gets up and goes along nice, while not putting too much pressure on anything. I might adjust some slack into the throttle, so that 1/4 throttle is all the way open on the twist grip. I also bought conduit on the way back to tie the motor mount into the oar locks for the extra support like so many do

 

[matt167]

Second trip was a success except the clutch in the Hangkai started to slip so I went in. I was running in the local hydro electric power dam and it has a strong current because of it, the motor was WOT just to make decent headway against the current.. I think the first trip the outer chamber was a little slack. But my $6 motor mount extenders which is just a 5' piece of conduit with the ends taped and holes drilled to bolt it togther. took the forces perfectly.

I think that it could take one of the 4hp's but it's sketchy enough I won't try it

 

[Fishcall1570]

If you really want to put the 4 horse on, and it sounds like you do, then install a plywood floor and fabricate a raised transom that extends over and aft of Intex mounts. The wood transom would distribute the forces through the surface area of the wood floor. That should help with "squish" above 1/4 throttle.Just keep in mind that at the end of all the redirection of force, it is still just an unsupported 30 guage pvc inflatable. Also, I saw that modification in a youtube video. You alreàdy heard the elders stance on what youtube is for.

Mailbox stickers for reg numbers. Clean and dry the hull well first.

I own one. I love it. I know what it is.

 

[matt167]

I think the modification is in one of the inflatable threads here as well.. It works very well. The oar locks on a Seahawk are in perfect plane of the upper motor mounts. On something like an Excusion that is wider, they may not be in the same plane.

The Hangkai gets the boat going about 5 MPH. I just have to replace the clutch. It's perfectly matched to the boat, and me and another person can carry the boat and motor all at once. I have an 8' pram that will be finished for next year and a 4hp is perfect

 

[Fishcall1570]

I have mine packed in my old sea bag. If I am close enough to the car to use the power pump, then I can get it smaller. I carry the floor like a brief case in one hand wich is a slight inconvenience but worth it for stability and the chair in the other. I am usually too shallow for motors or just go down too many rapids to make having to pull it up all the time worth it.

Hope you enjoy it!

 

[Lessismor]

I have an excursion with the 4 horse power Chinese motor w built in gas tank. I put longer tubes thru to rope knots along the back because when flooring it(4-5 mpg) it twists the top rear rubber inward like the motor is trying to fly over the rear of the boat or push it into a dive. Weight wise isn’t the issue, it just make the boat a little messy to handle. I love my inflatable

 

[leigamefisher7.5]

I have an excursion with the 4 horse power Chinese motor w built in gas tank. I put longer tubes thru to rope knots along the back because when flooring it(4-5 mpg) it twists the top rear rubber inward like the motor is trying to fly over the rear of the boat or push it into a dive. Weight wise isn’t the issue, it just make the boat a little messy to handle. I love my inflatable

Can the over powered boat pass the registration?