HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

da_q-ban_one

Seaman Apprentice
Joined
Apr 9, 2012
Messages
41
I would like to build a fairly inexpensive, but rather powerful 3-5 hp outboard for my Intex 4 Mariner Inflatable Boat pictured here:

http://www.allinflatableboats.net/intex-mariner-inflatable-boat.html

While rated to fit up to a 3 hp outboard, I?ve seen people put up to a 5 hp Merc and I believe that as long as I stay around a 45lbs and under motor, I should be fine.
With that said, I?ve seen a lot of people making their own home made outboards out of weed trimmers, lawn liners/mowers, etc, and wanted to know if anyone here has ever tried to modify one for themselves and more importantly, would share their step by step DIY.

Here are some starting ideas with Briggs and Stratton Vertical Shaft Engines with lower units (are all or most lower units interchangeable?):

http://www.youtube.com/watch?v=YFLdeJO6wfY&feature=related

There is also this guy who offers a detailed plan that seems both a bit underpowered and complicated to follow:
http://underwaterprojects.741.com/myfiles/Outboard.pdf

Can someone share theirs, or find a way to simplify the one above with more detailed instructions, perhaps?
Any inputs, comments or suggestions are appreciated. Thanks?

RT-
 
M

mrcrabs

Guest
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

I would stay away from home built conversions, all your going to get is a underpowerd piece of junk,
I see Tanaka TOB 300 and Gamefisher 3hp Tankas for sale on ebay that are like brand new for around the 300$ mark, thats your best bet for cheap and dependable, also the Eska clutch shift models fit your weight requirments just fine and run better than a briggs 4 cycle any day of the week if you could find one thats low hour in nice shape.

PS, The video;s and PDF especially the vid with the Ted Williams...very funny, the guy tosses a good marine Tecumseh 2 cycle engine out for a governed lawnmower putz engine....you have to be nuts and like to wast time to do this.....I say just buy a battery and a 50LB trolling motor and leave the weed eaters alone if your that hinky :facepalm: geesh..... in someplaces the Coast Guard will bust your butt for making such modifications to a marine engine
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

OMC 5.28ci twin outboards from the 60s and 70s, Evinrude Lightwin and the JW and JH series Johnsons, weigh in as low as 29lb. (JW-13). They can be had for $100 to $300, depending on location and season, even less if you are willing to bring them back to life.

They are far, far superior to any of the Rube Goldberg contraptions you have discussed. Smooth, quiet, economical, dependable. Best outboard ever made by anyone, ever.

If you want to reinvent the wheel you first gotta make them round.
 
M

mrcrabs

Guest
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

Yes a Lightwin, you couldn't get any better/lighter bang for the buck @ a 100 a hp, and there smooth as silk
 

twocyclemania

Chief Petty Officer
Joined
Aug 10, 2010
Messages
505
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

Another motor to consider if you're willing to accept a 2 horse. The little Evinrude 'Mates' (and Johnson's I believe) of the 70's vintage are great little motors. They're one cylinder but they do run nicely. I just picked one up that was missing the top cover with the recoil. Otherwise it appears to have been used only a few times. I just wrap a chord around the flywheel and she starts every time. You can almost start it by hand spinning the flywheel. The motors are quality built. I got mine for $40.00. They're also super light so I keep it as a backup in my 14' Aluminum. The Lightwins are really nice but everyone wants a premium for them and they're few and far between. Good luck!
 

da_q-ban_one

Seaman Apprentice
Joined
Apr 9, 2012
Messages
41
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

Thank you all very much for your input. I've been looking diligently for lightwins and those tanakas (both locally and on the internet), with no luck. However, I must admit that I am a bit weary of spending so much money ($400-$500 in some cases) on such old motors (lightwin and other vintage outboards that I've seen) which in some cases are listed as "running roughly" or "..does not start right away". I have been tempted to pull the trigger on one of those chinese/japanese knockoffs they are selling ebay and amazon branded "Hangkai", "Hidea", or simply no namebrand. Here are a few:

http://www.amazon.com/Two-Stroke-Ou...1_fkmr0_2?ie=UTF8&qid=1335342229&sr=8-2-fkmr0

http://www.amazon.com/Hidea-4HP-Outboard-Motor-Stroke/dp/B004CMMDHA/ref=pd_sim_sbs_sg_2

http://www.ebay.com/itm/160528894788?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

http://www.ebay.com/itm/170786162159?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

But I've seen some reviews of people complaining that these are hard to work on. However, they are really cheap!! Please share your thoughts.
 

da_q-ban_one

Seaman Apprentice
Joined
Apr 9, 2012
Messages
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Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

double posted... sorry.
 
Last edited:
M

mrcrabs

Guest
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

Let me just say in the words of someone I can't remember who,
Ye who expected nothing shall not be deceived
 

da_q-ban_one

Seaman Apprentice
Joined
Apr 9, 2012
Messages
41
Re: HELP!! Inexpensive 3-5 hp outboard ideas for inflatable HELP!

I bought one!!!!!

I found it locallly on craigslist, a 1992 Johnson 3 hp model J3RENM, and it was only $175. However I cannot find any info on this J3RENM, there seems to be a J3REN, but not a J3RENM.

I posted a new thread if you'd like to answer it here:
http://forums.iboats.com/showthread.php?t=545180

Thanks for all your help!!!
 
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