Ontarioflyer
Member
- Joined
- Jan 7, 2021
- Messages
- 10
I wanted to post this idea I had and get some feedback before I start testing. My 185's are not worth rebuilding (probably for the best) and I have decided to go with two GX200's on my Lazair. I have read many posts and saw the You-Tube videos with and with-out the re-drives. I know Ace-Aviation is the turn-key solution, but you know, price/shipping, etc. I have done the math with Torontogear for "timing belt pulleys and it is very do-able. Which brings me to my "plan-B" direct drive design. I don't have any cad-like software to draw something out, so I will do my best to explain the idea.
Depending on available crank shaft length, starting with one or two 3/4" split ring shaft collars directly next to the crank seal leaving a small space. Next is a 3/4" thrust bearing with the polished washer on each side. Four threaded rods (1.5 - 2" long) attached to the block around the crank-shaft that will hold a 3" x 3" x 3/8" aluminum plate with a 7/8" centered hole that will fit over the crank and fit up against the thrust washer, of course in the vertical position. So the split ring collar(s) are friction fit, the thrust washer will press against the aluminum plate as axial load increases. Then of course mount the prop on the crank in a direct drive application.
Honda will not give me the crank axial load specs (of course) and I am not a fan of the crank taking this load. I know the one re-engine Honda clone guy is having luck, but I suspect that it is just a "matter of time" before crank bearing failure will happen.
Thoughts, supporting math loads, nay-sayers welcome.
Depending on available crank shaft length, starting with one or two 3/4" split ring shaft collars directly next to the crank seal leaving a small space. Next is a 3/4" thrust bearing with the polished washer on each side. Four threaded rods (1.5 - 2" long) attached to the block around the crank-shaft that will hold a 3" x 3" x 3/8" aluminum plate with a 7/8" centered hole that will fit over the crank and fit up against the thrust washer, of course in the vertical position. So the split ring collar(s) are friction fit, the thrust washer will press against the aluminum plate as axial load increases. Then of course mount the prop on the crank in a direct drive application.
Honda will not give me the crank axial load specs (of course) and I am not a fan of the crank taking this load. I know the one re-engine Honda clone guy is having luck, but I suspect that it is just a "matter of time" before crank bearing failure will happen.
Thoughts, supporting math loads, nay-sayers welcome.