I run a 23m 14 1/2 Yamaha prop on my 97 150, rpms varied from 5200-5400 depending on weather, speed anywhere from 55-57. Purchased a spare prop that is the same and was reworked before purchase, tried it yesterday in the cool weather so I should have seen my max speed of 57.
I could only manage 53-54 but turning 5400 rpm, what is wrong or different between the two which would cause me to lose the top end but keep RPM? Pitch be off, cupping?
I'm no expert by any means so any info appreciated.
P to P to high for that particular prop or just not right for your setup
Thank You Leon Pugh
Originally Posted by lpugh
Sorry but is P To P, prop t pad? They are both the exact same prop, Yamaha 23M.
Yes 1st question. Doesn’t matter every prop is different. Was your original 23M “worked”? Drop the motor 1/8” and maybe the worked prop may bite better at lower depth. Hell you may need to raise it. What’s the max WOT RPM for the motor? Make adjustments to achieve that number.
Well I can't raise or lower the motor, there is no jackplate. Original prop not sure if it was reworked, bought used and guy had no answers as to whether it had been done before. Max RPM for motor is 5500.
I can achieve 5400 with both props in the cooler weather. I can even reach that with my 24 pitch prop. Speed the same from original 23m as with the 24.
Hence my question, if the rpms are the same and I'm at my max what do I need to do to this new prop to increase speed but not RPM? 3 mph is alot of speed loss for me. Thanks.
Out of the box, prop vary all over the place, Get all the baseline information regarding your rig an contact one of the top prop guys to prep that prop for you rig and what you wish to achieve from it. Used props can be disaster, You don't know how badly some one may screwed them up or how many times the blades have been reworked and bent.
I would never buy a used or reworked prop without knowing its history and running it first
Thank You Leon Pugh
Good info to know, I figured a 23 m was the same as the next one. Probably send this to Croxton prop as I keep hearing about them. I've had 3 reworked around Ontario an not impresses with any of them, but I 'm hard to appease.
At 5500 rpm's all your going to get is 57 mph max. If the old prop is doing that I wouldn't have it worked. That motor has a 2.0 gear ratio and you would have to turn a bigger prop to get more speed maybe a 25 m.
I can run 58 with my 24 at 5300 rpm, 57 with original 23m at 5400 and 55 with the "new" 23m at 5400. I only achieve those rpms in cooler weather, all summer its 5200. Had a old Suzuki 24 prop that threw an ear at WOT and it was a 59 MPH prop for me.
Max is supposedly 5500 but I have no issues going to 5700 if needed.
No jackplate so adding one would help as it runs maxxed out trim. Jackplate in the future but not for at least 2-3 years
It has the 1.86 ratio I don't think I can turn that 25 to those rpms.
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