Re: Prop Step Up
Posted: Thu Jan 17, 2019 2:57 am
The slippers have oil cups and work fine, but the top bearing is bronze and hardened steel w/ grease and the big end (not big enough) is bronze w/ an iron crankshaft, with a rubber line and and 18" of head from a oiler. The bearings won't take the pressure, and wear quickly, which is why Otter doesn't participate in races and we cruise at perhaps 100 psi. A good thick lube oil has helped on the big end.TriangleTom wrote: ↑Wed Jan 16, 2019 10:34 amBart-barts wrote: ↑Tue Jan 15, 2019 4:17 am
Otter has the same problems w/ her 2.5" x 2.5" single as the counterweights are too small; the old 2" x 2.5" single acting twin was much smoother at speed, of course. I went to a 16"x20" prop from her old 13" x 17" because the new engine ran away w/ the small prop, but at full throttle (180 psi) the crosshead and big end bearings really hate me.
- Bart
I'm curious what you're doing for crosshead and big end lubrication that lets it stand up to that much pressure.
This engine is 100 years old, and I had to redo the top bearing when I got it as it was worn out, and the big end needed adjustment as well.
- Bart