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roda
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I have a 2005 MC197 non-slot that came w/ a 12x12.5 OJ prop.  PPC

I hit a turtle and bent a blade.  Gave it to the local MC dealer which uses a local prop guy to fix.  After it was returned I ran through the course and it seemed a bit fast at 34 even though I didn't have a skiier so I did a quick calibrate on it.  The next morning we skiied and I noticed right away that I could hear the engine reving more than usual to adjust for the skier (200lbs 28off).   When another skiier @ 32 mph skied it was running 34mph times before I calibrated it.   When we were done I ran through the cals on times down to 26 and they were all quite fast on the first cal pass.  When back on the lift we looked at the prob then compared it to my neighbors exact same boat and we noticed that the refurbed prob had a much more defined lip or curl on the back of each blade.

Boat seems to be running good times but just wondering if anyone has any opinions on if this is typical???  A 2mph swing on a simple repair seems a bit much to me.

 -Rod A.

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The prop guy put a different cup(that curl that you're talking about) on the prop than what came from the prop manufacturer. Not necessarily wrong or a bad thing. Just different. Different cups will give different speeds and wake characteristics.  A lot of times a prop guy, based on his own experiences with a certain boat and prop, will cup them differently. Sounds like the cup this guy used is a bit more efficient, which resulted in a higher speed for a given engine rpm.  I'd back the rpm down in your calibration and have at it. If the skiers do not notice a difference, I'd call it good. The only bad thing would be if the lower rpm took the engine out of it's power band but I doubt that's the case as cupping usually only affects things by a couple of hundred rpm. I believe OJ has two props in that size for that boat. One has a .090 cup and the other has a .110 cup.
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As mentioned, the reconditioned prop has more cup than the prop had previously.  The effect is basically the same as adding pitch to the prop.  Correctly stated, you will need to recalibrate an rpm based speed control system as it has changed the speed to rpm correlation.
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