Horizontal shaft boat engine

[KVF 700]

So I have been quite intrigued by some boat motors ive come across on the net. They are often referred to as "mud motors" or "long tails". They utilize an ordinary horizontal shaft engine between 5 and 35 hp. Basically just couple a long straight shaft to an engine and put a prop on the end. You may have noticed that the prop will run at a bit of an angle, but these props are specially designed for that. This setup is mounted on a shallow hull boat. See photo.

I happen to have a 24 hp Honda v twin. This kind of set up looks relatively easy to make. I need a couple opinions though. First, I think it would be easier to build the shaft using bearings and a small framework, rather than enclosing the shaft in a tube, like seen in this crappy you tube video.

http://www.youtube.com/watch?v=0sJJ3Kw9qv0&feature=youtube_gdata_player

But would the shaft start vibrating to much once you start spinning it at 3500 rpm?

Second, would something like this with a heavy duty mud prop and rock guard, be useable on small rivers?

Share some opinions. Yes I realize it's easier just to go buy something but that's not the point.

Here is an example of one in action

http://www.youtube.com/watch?v=eNbL8YjfG_g&feature=youtube_gdata_player

 

[TROLLCAT]

in close the shaft or it will grab stuff and whined it up 'eg' rope , weeds , people , fishing line ,

 

[KVF 700]

That is a good point. Not planning on using it as a "mud boat" or anything like they show. Just like a normal boat in regular water.

 

[kbweed]

i used the mudbuddy motor and a 14 foot heavy jon boat a fair bit this year. amazing is all i can say, i own a jet boat and love it but these motors will take you anywhere. there are draw backs though you are not able to go very fast and they are not very manuaverable and the lack of reverse sucks. but they can go through anything, iff you get weeds on the prop just lift it till it cavatates and it will spit them off.

 

[kbweed]

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[007sevens]

didn't Sly use a v8 in his last Rambo movie? That should get up some speed.

 

[eclipse1966]

not exactly the same but the use the long shaft props in the waterways throughout Thailand. Thousands of them in shallow waters. Some have them hooked up to 4 cylinder engines that are mounted on a center pivot shaft to the block.

 

[tukernater]

they use those motors in that show swamp people.