My 98 Mackinaw has a slight vibration just before getting on a plane, I can see the shaft log run-out at this point then it disappears by 20mph. A new prop, new cutlass bearing and coupling alignment to within 0.003" did not resolve the problem. I suspected the shaft may have some run-out but put it off due to the horror stories of coupler removal. Last week, I built a heavy duty puller based on designs for sale, it is 1/2" plate with a 3/4" NF bolt and nut. The coupler pattern for my Liberty 5000 transmission was easy to find and simplified the project. Fortunately for me, with the help of a 1/2" impact gun, the coupler budged and I had the shaft out in about an hour.
I took the shaft and coupling to Ryan at Wilmington Iron Works for inspection and repair. There was only a small amount of run-out in the shaft to repair then reface the coupling. The shaft and coupling looked great and included new keys, set screws, and paint on the coupler.
I tested the boat with a different prop from Damon ( 17x14 3 blade) vs the previous prop (15x15.75 4 blade). The results were good at low speed and the boat practically jumped out of the water, but the prop also produced a new vibration or harmonic at higher speeds that was troubling. I have since reinstalled the 4 blade and will retest when weather and work permits to verify if the issue was due to the prop.
Rough looking, but it got the job done! I'll make it look nice when I have time

Shiny like new!

The big wheel, I had high hopes for!
I took the shaft and coupling to Ryan at Wilmington Iron Works for inspection and repair. There was only a small amount of run-out in the shaft to repair then reface the coupling. The shaft and coupling looked great and included new keys, set screws, and paint on the coupler.
I tested the boat with a different prop from Damon ( 17x14 3 blade) vs the previous prop (15x15.75 4 blade). The results were good at low speed and the boat practically jumped out of the water, but the prop also produced a new vibration or harmonic at higher speeds that was troubling. I have since reinstalled the 4 blade and will retest when weather and work permits to verify if the issue was due to the prop.
Rough looking, but it got the job done! I'll make it look nice when I have time

Shiny like new!
The big wheel, I had high hopes for!
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