92 Explorer & F250 Prop

shoebob

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Just put a 2006 F 250 on the back of my 92 24 ft. Explorer.... The Engine came with a Yamaha Prop pitched at 21in.. I'm on turning 5400 RPM's..
What have others done with this configuration? Any Spec's out there?

Thanks....
 

Doc Stressor

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You need a 17" pitch prop. That should bring you up closer to 6000 rpm, which is where you need to be. The F250 does not do well when it's over propped.
 

shoebob

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Doc, thanks.... But if I would gain 200 RPMs for every inch of pitch wouldn't I be over where I want to max out at, ie 6200RPMs. ... And with a 19 pitch I'd only be at 5800... Been told to stick with Yama. props, that they are worth the money, but they don't go with an 18 pitch in the saltwater series....

Thanks Again..
 

Doc Stressor

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Your probably getting a lot more slip with a 21" prop than what you'll get with a lower pitch prop.

I've seen several 24' Grady's with 250 hp engines and they were all running 17" props.

For reference, my 22' turns 5800 with a 17" Yamaha SSII prop on an F250.
 

seasick

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shoebob said:
Just put a 2006 F 250 on the back of my 92 24 ft. Explorer.... The Engine came with a Yamaha Prop pitched at 21in.. I'm on turning 5400 RPM's..
What have others done with this configuration? Any Spec's out there?

Thanks....

I wouldn't fret over WOT as much I would be over performance. The WOT range for that motor can be anywhere between 5000 and 6000.
Your prop selection should be based on your needs. For example maybe you troll more than run wide open. Maybe you usually carry a bigger load like all your fishing buddies. Maybe you need better low end torque etc.
Bottom line is that there is no simple answer. In fact different props (manufacturers/model lines) with the same overall specs can perform very differently.
My advice is either find a really good prop shop that asks the right questions or talk to folks who have the same boat and motor and use it like you do. Ask what prop , make model and specs, they have and how well it has worked out. Use that as a basis for your decision.

Enjoy and safe boating.
 

shoebob

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FYI.. for anyone else upgrading like I did, Doc called it, the Yamaha 17 SWSII nailed it..

I was leaning to a 19p, but with recommendations a went with the 17.. Final results were top end
5800 rpms... Best cruise 4700 / 29mph / 2.4 mpg.... Assuming I only gained 400 rpm's going from a 21p to a 17p due to the increase in diameter .. 3/4 inch....

Thanks again Doc...