Classic AquaSport
Aquasport Mechanicals - things that need a wrench, screwdriver or multimeter => Props => Topic started by: Go Deep on May 14, 2007, 10:47:18 AM
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I have an older 19'6 with a 125 hp engine. While I was able to get the boat on plane and up to 29 MPH (GPS), she was sluggish getting there. Is this a pitch problem? what should the prop pitch be? Thanks...
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What RPMs is the engine turning at top speed? What prop are you using (how many blades, diameter, and pitch)?
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I had to reprop my 150 hp blk max recently for use on my ccp 222. it was previously on a 18.5 ft Nitro lake boat. I had to go from a 4 blade 22" to a 15.5". I don't have the pitch # in my brain rt now. The key thing to do is determine your engine rated max rpm & prop to achieve that rpm at wide open throttle. Failure to do so will result in under or over rpm @ WOT, either of which can destroy your engine for different reasons. Sluggish out of the hole can usually be helped with max trim adjustments. I used a jack plate with 4 degrees of negative trim shims added to the top mtg bolts to 'tuck' the prop deeper under the stern. We were out last Tuesday, 4 people, 85 gal of fuel & several coolers of refreshments & ran 42 mph @ 6000 rpm on gps; 30-31 @ 4500 rpm & 8mph @ 2200 rpm. 10 gal/hr @ 6000 rpm & 5 gal/hr @ 2200 rpm. I love this hull/boat. :D :D