Alex F
Well-Known Member
- Nov 14, 2006
- 9,166
- Boat Info
- 2005 420DB with AB 11 DLX Tender, Raymarine Electronics (2x12" MFDs) with Vesper AIS
- Engines
- Cummins 450Cs, 9KW Onan Generator, 40HP Yamaha for tender.
Great thread! I have the 480CE which is really the same engine with the first attempt at computer control. I have gone through the overprop issue from Sea Ray. my factory props were 23x27 4 blade hytorq. After a dropped valve seat in the stbd. engine I was advised via boat diesel to take out two inches of pitch. I did that but found I was then under propped. Ultimately I switched to new Acme's. During this process I found out that Sea Ray used a large amount of cupping. .130 I was told that each .030 of cup would result in 45 rpm. So if anyone is looking at a re-pitch have your prop guy check the cupping as well.
Mike,
What was your WOT RPMs with 27" pitch and what was the result of the adjusting it to 25"? I'm running HyTorque 23x26 with #.11 cup. My WOT range 2680-2700.
Also, what's your experience with Acme's?