Welcome! Need support, you got it. Or share you ideas and experiences.
In Reply to: Re: Great Forum!! Thinking of building an outboard posted by machnumber2 on July 16, 2003 at 23:22:44:
Thanks for the great advice. I've checked out you and Ken's previous discussions and pictures, and it's been a great help to me in visualizing my plans. I'm looking forward to hearing his input also. I do have sketches written out. I just need to scan them, and i'll post them to be seen. I really like your idea of using an outboard lower unit. I just hope i can find a good one i can afford. You're right, I spoke with and friend who's an outboard mechanic, and it's very unlikely for the motor to over rev. I'm trying to figure out the wot rpm at full load, I'll let you know once i figure it out. Then, the lower unit size can be figured out. Thanks for the formulas. You're math looks pretty good to me. You're also right about the 1.57 gear reduction. I'll also be posting pictures as I begin. Since my brother is a welder, I'll let him tackle the welds. I can tack up some pretty uly "buggers" on my attempts :) I'll fill you in with more information soon, as I figure it out. Thanks a bunch!
CC,where are you!?
Lets get this show on the road, we want to see this thing develope and work and are here for you if we cant help in anyway. Get yourself a digital camera and post the progress here, or zip your photo files, email them to me and I will post them for you. Cant wait to see this project.
Wow, you guys are on the ball! I apologize for acting so slowly on my project. I've been doing a lot of fishing with my dad to help him recouporate from several surgeries. Good news. . . it's working :) The fish in our area are really biting right now, and we're enjoying it. I've been trying to locate a small lower end at an afordable price and I'm having no luck. For the price people around here want for a small lower end, I can get a whole outboard for the same price. I'm looking at this working older model 9.5 Evinrude that is affordable to me. Hum, to buy or to build? I'd much rather build :)
I'm also still trying to figure out the wide open throttle rpm at full load for this 3.5 hp birggs. Briggs and Stratton is supposed to contact me with the info. Is there a way I can find out this info myself? Can I hook up a tach to the motor? Sorry, if these questions may sound stupid . . . this is one area I'm not familiar with. One more question guys. How do I post pics on here? Or would it be better just to link the pics to my website. I'll be back soon with the pics! I just got a digital camera :)
Ebay is a great source to find used outboard parts. here are some that I found for $10 to $30,
Briggs does not seem to make thier tech data readily avail on the internet but if you ask enough people you should find out soon enough. Better yet call some repair shops and ask them.
You can get a tach for those motors, its called "tiny tach", I think its like $50 though. You might be ok just to assume 4000 rpm for the briggs and 6000 rpm for the 2 stroke. If you do for your 3.5 hp it would be 3.5*3800/2500 = 5 hp lower end from the earlier calcs if they are valid. The way I see it is that you may not be able to buy a lower end with hp that exactly meets your calcs. Maybe anything from 3-10 hp lower end would work good enough.
When I posted photos I would just past in a link to my webpage.
Wow! Thanks for the ebay links. All of these lower units look pretty good. I really like the mercury one. I have some bad and good news. Looks like I'm going to have to use this briggs to build a generator instead of the outboard. Hurricane season is upon us, and the generator will be more useful to keep the freezer running (Last season we lost all of our perishables due to hurricne Lily). So, I've put my outboard plans on hold for now, but I still want to build this outboard. I want to try to make the motor interchangeable to be used as the outboard and generator. So, I'll keep you posted as my progress goes on both projects. I know this is a boat forum, so I'll post info about the outboard and post links to get to the generator info at my website. The good news is, I found a little 97 6 hp mariner for our little flat boat. So, now we'll be able to fish in better areas :) Thanks a whole bunch machnumber2. You've helped me a ton! :) Oh yeah, I'll be calling our local briggs shops tomorrow morning to find out the wot.
Well have to say that I am disapointed but this generator could be pretty neat. Post the details when u get a chance.
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