Aquasport Mechanicals - things that need a wrench, screwdriver or multimeter > Props

Prop(pitch/size) question

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Flapilot:
222 semi V light weight no tower.
Suzuki 175
Current prop 3/15/21

I feel like the motor is running too high RPM. I can over speed it at full throttle trimed out and porta bracket set so skid plate is just right sitting on the water.

I mostly fish inshore Tampa bay on the flats so planning out quicker is my bigger concern over top speed.

Suggestions?  Does it sound like I’m propped wrong to you guys?

Levi:
You can be underpropped and it won't harm the engine but if you're able to get over 6k rpm then you should step up in pitch. Your holeshot shouldn't be reduced but your top speed should improve.

Flapilot:
Thanks!

boatnamesue:
Not familiar with zuki's....refer to your service manual for the spec rpm range @ WOT.  You want to be at top end of spec, testing with a light load and calm conditions.  If you're turning higher than spec....I'd first verify this using a secondary rpm source before investing in a new prop.  If rpms are verified higher than spec, the rule of thumb is for every 1" of pitch = 150-200 change of rpms.  Increase pitch inch to lower rpms, vice versa to increase rpms.

GoneFission:
Most engines today won't let you over-rev.  They have rev limiters set for max RPM.  Check your manual and see if you are on the limiter.  If so, go up a couple inches in pitch.  You didn't say if your Zuki 175 is a V6 or inline 4, but I think both go on the limiter at 6,000 RPM.  The inline 4 should run about 5500 RPM WOT with the right prop, and about the same for the V6, although the V6 has a wider power range and you could be as low as 5,000 and still be OK.  Consider a higher pitch prop for sure if you are running above 5500. 

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