Has anyone tried this?

Ok so this might sound a little bit crazy, so here it is. I have a 24hp Briggs & Stratton v twin that is still attached to our old riding mower, about the only good thing about the older mower is the motor it still runs like new (Deck, transmission???, steering, belts, tires etc..is bad) so the Idea was to use the motor on an older outboard as the new power head. My dad who is mechanically inclined suggested this as something he wanted to do after seeing a few videos on YouTube. I'm not wanting a mud motor here just a reliable outboard with forward neutral and reverse. My questions are
1 What midsection and lower unit to look for ( looking for a motor that is easy to get parts for cheaply )
2 I know motors have to have spark arrestors on the exhaust would the stock muffler work for this or will I have to figure something else out?

3 Our local boat mechanic has a large parts yard and upon asking he shows us around to an 87ish Suzuki Dt25, the power head was ??? but the midsection and lower unit were still in good shape he was asking around $200 is that a fair price or outrageous? He also showed us to quite a few but quite older motors too.
The lower unit will need new seals after setting for X# of years. Also he said that the Suzuki's had near bullet proof lower units; is this true?

Just looking for some advice on this concept I've seen it done on smaller motors but never one of this size.

Never done this


How much doe your motor weigh?

[url=https://www.tinboats.net/forum/viewtopic.php?p=347518#p347518 said:

Captain Ahab » 05 Apr 2014, 05:54[/url]"]Never done this
How much doe your motor weigh?

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Don't know actually, haven't taken it off of the mower frame yet. Doesn't look or seem all that heavy. I think when it's all said and done the outboard will weigh about the same as a new twenty horse 4 stroke. My dad wants to get a motor with power tilt and trim & I cant agree more.

Also Since the motor is air cooled I wont have to worry about overheating because of shallow water or trash getting sucked up and it has never been finicky on fuel even ethanol fuel doesn't seem to make the motor run rough + I've taken fuel that my Tohatsu 4hp 4stroke wouldn't run on and this engine runs just fine on it. Plus it's electric start & I've always changed the oil at the proper hours, though it might need a new starter solenoid the connection was always a little iffy ( just a little jiggle and the motor would start). When me & my Dad tackle this project I'll be sure to post the details and progress + the final result. Got to find the right parts motor first to do this conversion. So until then any advice or input would be helpful. I don't mind criticism so go ahead and give me your full opinion.

Many years ago I saw a small mtr done like this. Looked like from a push mower. Don't know how well it worked but was cool looking.

My first thought is: Why would you want an air cooled motor when cool water is right there to use? Lawn mowers only have air to use.

That's going to be a big, noisy, HOT, power-head right next to you on the boat...with hot exhaust pipes and a hot muffler...with hot air blowing around. It will not be as pleasant to run as a nice, cool, quiet, water cooled unit.

If your engine is in really good shape, maybe it can be sold for some good money. Mowing season is just beginning. Your engine might be the same as the commercial guys use. Put the money into a good used outboard motor. Use that massive amount of time(and ingenuity) to search out a clean used engine.

Don't get me wrong, I like a good experiment/project as well as the next guy. It just seems like a long up-hill footrace and your starting off with a nail in your shoe.

I really don't like being the voice of discouragement. You did ask for the full opinion. I've taken a lot of dirt roads where I should've just stayed on the pavement.

Whatever you decide, I hope it turns out well.

Already tried to sell the mower plenty of times; to many lowball offers. This is not the commercial motor though that may be why. In my area there are a lot of good running mowers for sale so not to many people wanting to buy just a motor. Found these pics online my Idea brought to life so here are pictures to kind of show what I'm going for. This outboard is using the same air cooled 24hp Briggs & Stratton that I have.

This guy put it on a 40hp mercury midsection & lower unit. I think a 25 or 30 will work just fine for me.

guy said it did 32mph on GPS. It looks like it works pretty good to me

My dad wanted to do this as a father son project, I showed him a couple of videos on YouTube he was gun ho on this concept. I'm not in the market for a new outboard as I am contempt with my fuel sipping 4hp 4stroke Tohatsu ( 2011 model bought new in 2013 ) It's not the fastest but it's perfect for fishing in large sheltered creek arms and a local 500 + acre city water lake. But I think this will be an interesting project nun the less.

If you could fabricate an exhaust that entered into the mid-section, most of your noise would exit through the prop. I lost my dad a few years ago, I'd give anything for one more project...

[url=https://www.tinboats.net/forum/viewtopic.php?p=348143#p348143 said:

mphelle » 10 Apr 2014, 01:32[/url]"]If you could fabricate an exhaust that entered into the mid-section, most of your noise would exit through the prop. I lost my dad a few years ago, I'd give anything for one more project...

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Sorry to hear about your loss. I don't think it will be any louder than a traditional mud motor though this is a good idea to reduce noise. Going to look into this one. Thanks for the advice.

I have the same motor on my craftsman mower. It's 8 yrs old and runs great w 160hrs and has plenty of power.

[url=https://www.tinboats.net/forum/viewtopic.php?p=348467#p348467 said:

juggernot » 12 Apr 2014, 23:01[/url]"]I have the same motor on my craftsman mower. It's 8 yrs old and runs great w 160hrs and has plenty of power.

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My motor has nearly 500 hours on it. 476.5 to be exact. Still runs like new. Ours is seven years old, it is a DYS 4500 with a 42 inch deck. Last year we got a new mower one with a 26hp Kohler and a 54 inch deck. Our old mower was put through some abuse more than its fair share actually, mowing 5-6 acres at a time. The hydrostatic was having some issues, though they say non serviceable through a little research I found out it could be serviced ( sears can say this for the estimated life of the transmission (500 hrs) ) Well since it was just sitting around we decided that making an outboard out of it would be a neat yet functional project to do. The motor still runs almost like new so it will still provide plenty of power. Always kept the oil changed at the intervals mentioned in the service manual. Always used Pennzoil 10W30 in it. Going to ditch the stock exhaust & muffler though. There is a huge aftermarket in the area of lawnmower racing and mud motors. Going to try and find something that sounds like this https://www.youtube.com/watch?v=ioTFkCEpz-c