Home Small Boat Forum

Welcome! Need support, you got it. Or share you ideas and experiences.

Re: Homemade outboard motor using briggs 2hp

I do not think the bearings I saw will be able to hold the shaft without some modification. Question, Are those bearings designed for taking stress from a left to right perspective on the shaft in your diagram? If they are, I would try drilling the shaft, to let the set screws actualy enter a so called set screw hole on the drive shaft, Might also look at stonger material, becuse now,, thay are more acting like shearpins then set screws.or perhaps, grind little flat stops on the shaft where the screws contact the shaft.
Thrust bearing, Yeah that would probably make it much stronger, Might be some other way you could get around that besides drilling the shaft or grinding as I sugested. If they are cheap, Its probably the best way too go.
In your math you mentioned it you would require all of the 2Hp of the motor to acheive the 5mph.. But isnt Prop horspower somewhat lower then actual Engien Hp on most outboards? or do I have this backwards. Also, the weight of the boat gear, motor etc dont seam to be in the equation. I supose it could be irelivant when trying to figure stress on the shaft.thrust is thrust, but does how much it is pushing affect the stress? I guess I estimate more then reli on math in most circumstances ;p And I would estimate that about 2 Hp would produce about 55 pounds of thrust, But mind you that is indead a estimate. I dont think you have told us yet how big the boat is you are using. Are you planning to pipe the exhuast underwarer?

This post is made possible by the generous support of people like you and our sponsors:
  K&K Audio / Lundahl Transformers   [ K&K Audio / Lundahl Transformers Forum ]

Follow Ups Full Thread
Follow Ups

You can not post to an archived thread.