Props with better grip?

RDCGrady

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I have a 283 release with twin Yamaha 250's. I like the twins but wish they could perform a bit better in terms of control during docking especially in windy conditions. I noticed that Pursuit boats have their engines spaced a bit farther apart than on the Grady's and would assume that helps with the control issue. Obviously, inboards are even better with their big aggressive props.

Does anyone know if there is a prop I can change to that would give the engines a better bite on the water? I don't really want to change the performance characteristics of the boat except at slow speed or make my fuel efficiency worse.

Thanks......
 

NOTHING ELSE MATTERS

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A trick i was told(if you backing in to your slip) by somebody is when trying to dock and have one motor in reverse and one foward, the motor in reverse should be in much higher rpm, maybe up to 1500 depending on the wind, and you control the boat with only the other engine, foward if you want to turn,reverse to straighten the boat. I hope it helps. As far as inbords, is not much the size of the props but the location. I had a diesel boat with same size props i have on the f250's, and it was day and night as far as docking it.
 

seabob4

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That little trick is called "splitting" your shifts. Should you choose to back into your slip from a starboard approach, say, put the port motor in reverse, the starboard in fwd. The port motor will pull you to the finger pier, the starboard motor will push your bow towards port, thus straightening you out. A "pivot" effect. Should you not be fighting major current/wind issues, then it is a matter of backing in with one motor in reverse, the other in neutral, as it's not needed. Practice, practice, and more practice. And don't be afraid of using the wife/whomever to fend off. After all, there is not a panel of judges sitting nearby to grade your docking performance!

Your 283 probably has the motors mounted on 28"-30" centers. Pretty typical of this size boat. It's not the props, it's the technique.
 

RDCGrady

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Thanks for the replies.....I appreciate the input. Brian....I don't know what size the props are. I think they are Yamaha Saltwater series and are whatever Grady puts on those boats at the factory. I will check the size the next time I'm at the boat and will let you know.

Thanks,

Bob
 

gw204

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At slow speeds, the most important thing is to have large diameter wheels. I went from 14 x 19 Yamaha SS 3-blades to 15-1/4 x 19 Merc. Mirage Plus SS 3-blades on my boat and noticed a huge improvement in "around the dock" handling.

Someone correct me if I'm wrong, but I think the Yamaha SWS props are already like 15" diameter wheels, so going to something different will most likely not be worth the expense unless you can get improvement in others areas as well.
 

ocnslr

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gw204 said:
Someone correct me if I'm wrong, but I think the Yamaha SWS props are already like 15" diameter wheels, so going to something different will most likely not be worth the expense unless you can get improvement in others areas as well.

You are correct.

The Yamaha SWS series are 15.25" diameter.

The SWS II series range from 15" to 15.75", depending on pitch.

The Reliance SS are 13.75 to 14.5.

Brian
 

enfish

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Any drive system with exhaust that comes out through the prop hub is not going to have as much bite in reverse because the prop is spinning mostly in exhaust gas.

My previous boat had an old OMC outdrive with a 14x14 prop. The exhaust on that drive came out the anti-cavitation plate, so the prop was always in clean water, even in reverse. I could stop and spin that boat on a dime. It took a while to get used to the fact that I couldn't stop my Grady as fast.
 

RDCGrady

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Brian...I took a look at my props and it appears they are 15 inch with 21 pitch.

Onoeric...interesting about the exhaust creating a difference in the prop's ability to grip.....thanks for the input.
 

ocnslr

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RDCGrady said:
Brian...I took a look at my props and it appears they are 15 inch with 21 pitch.

A 21" pitch seems high, even for those powerful F250s.

What WOT RPM are you able to achieve?

Are they Yamaha props? or ????
 

BobP

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Just think how it would be with the Sailfish model of your hull instead of the CC, with all the extra cabin and canvas windage ?

I observe many times captains are too timid working the throttles in reverse. They expect more response as if going forward but don't want to add too much throttle.

With windy conditions across the beam, we are all in trouble with these relatively light & longer boats not benefiting from the inertia and more displacement of the heavy big dogs and their props placed back under hull and spread further.

If you are backing in, or forward entry, and depending on from how far out you have a clean approach and from what angle of approach available, the wind takes the bow, nothing the twins or single can do. On backing in, you have move fast enough to prevent the bow going downwind too far, so just get the stern into the first set of pilings, then use the leeward side piling to pivot off, turn the wheel hard to leeward and lean on the reverse throttles, the bow will stop going with the wind and come back around very slowly against the wind and then you can back into slip all the way, have to lean on throttles as hard as you need, no ime to be timid, and make sure you lift up trim a bit, not too much. You have a lot of twin power at your disposal by directing thrust with steering, so lean on throttles, you won't damage anything.

If you are going in forward, easier, just get the narrower profile bow between both pilings, then the leeward piling will hold the bow while you power in, turn wheel to bring stern back into wind and straighten out as you go in. Stop the boat with hard reverse throttles.

The wind's effect on the boat primarily the bow makes it beneficial to be deliberate and move quick, not like the big dogs who can stop the boat and linger in, seemingly as if no wind is there.

When it's windy, throttle steering to control the bow is no match for wind and you will run out of time trying to recover as you watch the bow go like it is out of control (that's because it is).

Another good thing about counter-rotator twins, no matter how hard on throttles forward or reverse, the stern will not want to push sideways.

For two years I was in a slip to back in, slip was just one foot wider than beam, where I had to approach at 90 deg and turn at the right time, sometimes it would take several aproaches before I made it between the pillings, and sometimes couldn't do it since the boat refused to turn hard enough to move the bow out, had to go bow in and redock later when it calmed down.

When it is calm out, you can stop the boat, and the bow will stay put, then linger in using throttle steering if you prefer, no need to rush - you have all the time in the world. Crawl in like the big dogs.

Practice, practice, practice, and get a bow thruster on next boat.
 

RDCGrady

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BobP..thanks for taking the time to send all that good information....I'm glad I'm not dealing with a 282 in the wind!

Brian...I checked the props today and they are Yamaha Saltwater Series 15 inch with 21 pitch. I don't know what I get a WOT as I've never tried....perhaps I'll give it a shot if I find a calm day with little boat traffic.