I have a large RIB that I purchased with an existing prop and set up a couple of years ago. I am now in need of selecting another prop and would like to ask which choices may make sense for my application. I have read a bunch of these posts so I likely know just enough information to get myself in trouble here but I will give it a shot anyway. My goal is to get a relatively 'cheap' prop that will allow us to use the boat for recreational cruising and also for some water skiing and toys.
Boat is a 2002 Nautica RIB , flushdeck, 19' long, 8" 2" beam , total weight rigged to use is 1,575#'s, it is a deep V with a stepped flat center hull at the rear. Boat is rated to 150 hp max. , 3,200 #'s , and 16 pass max.
Current prop is aluminum , 3 blade, marked 12 3/4 - 21" on the inner center hub, no manufacturer marks, white, good condition.
Motor - 2002 Yamaha F115 4 stroke, 2.15 lower , good condition, tach checked w/ strobe. WOT range is 5,000 - 6,000.
Mounting - currently mounted with antivent plate even with flat center keel. Was mounted 3/4" higher (2nd hole) then keel when originally purchased but prop would blow out at all trim settings other then almost all the way 'in'. There are no doel fins, trim tabs, or other 'stuff' back there.
Current performance - with 3 pob , 3/4 fuel (more then normal) - we can always reach WOT of 6,000. With trim all the way 'in' we plow pretty badly and get 5,800 and 45 mph (gage only, not verified) , at about 1/2 trim 'out' we get 6,000 rpm + and a gage reading of 52 mph, at full trim out we still get blowout but at a second or 2 trim in from full out we get 6,200 rev limited. It will plane and cruise with 6 -8 adults on board with no real issues. We have no problems pulling a skiier at about 3,500 rpms on slalom. What are my options and what else can I do to help determine this?
Thanks
Boat is a 2002 Nautica RIB , flushdeck, 19' long, 8" 2" beam , total weight rigged to use is 1,575#'s, it is a deep V with a stepped flat center hull at the rear. Boat is rated to 150 hp max. , 3,200 #'s , and 16 pass max.
Current prop is aluminum , 3 blade, marked 12 3/4 - 21" on the inner center hub, no manufacturer marks, white, good condition.
Motor - 2002 Yamaha F115 4 stroke, 2.15 lower , good condition, tach checked w/ strobe. WOT range is 5,000 - 6,000.
Mounting - currently mounted with antivent plate even with flat center keel. Was mounted 3/4" higher (2nd hole) then keel when originally purchased but prop would blow out at all trim settings other then almost all the way 'in'. There are no doel fins, trim tabs, or other 'stuff' back there.
Current performance - with 3 pob , 3/4 fuel (more then normal) - we can always reach WOT of 6,000. With trim all the way 'in' we plow pretty badly and get 5,800 and 45 mph (gage only, not verified) , at about 1/2 trim 'out' we get 6,000 rpm + and a gage reading of 52 mph, at full trim out we still get blowout but at a second or 2 trim in from full out we get 6,200 rev limited. It will plane and cruise with 6 -8 adults on board with no real issues. We have no problems pulling a skiier at about 3,500 rpms on slalom. What are my options and what else can I do to help determine this?
Thanks