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Do I have the wrong pitch prop?

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Old 06-23-2003, 11:00 AM
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Question Do I have the wrong pitch prop?

I recently got a 22' Warlock SXT (cat) and it is using a Bravo I out drive and will not come up on plane. The prop is a 30. All the boat want to do is dig down in the stern and rise on the bow no matter what trim level. Anyone else have a problem like this? Do I need a different prop? HELP PLEASE! Any suggestions?

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Old 06-23-2003, 11:04 AM
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I am not a Cat expert but what Size power etc? Did you just buy the boat? How did it perform with this prop before?A 30 pitch on most boats will require quite a bit of power .


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Old 06-23-2003, 11:07 AM
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Unless you have BIG power as in over 700 hp, that prop is way to big. Step down to a 26 and see what happens.
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Old 06-23-2003, 12:22 PM
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have approx 650 hp. Hope a 26 wil help.....all the 30 wants to do is dig the stern in.
 
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Old 06-23-2003, 12:38 PM
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It came with that prop on it? Sounds like the previous owner had a secret to getting it on plane, like maybe getting it to cavitate a bit by lots of trim, and tabs way down. I guess once you get it on plane, you can tell if you have the right prop to scare the rev limiter.
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Old 06-23-2003, 01:34 PM
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What is the drive ratio? I have a 26' cat and with a 30" Bravo 1 prop, 1.5 ratio and 600hp, and I found that it was actually too small. I stepped up to a 32" and found 5mph. If you have a 1.5 ratio drive a 26 will be laughably small. That will not be true with a 1.36 drive. I found that the 30" planed pretty good, but that the 32 was really sluggish. Now I'm running a extension box which will help big time with the planing. But they arn't cheap. Also, your boat proably will not plane out unless the drive is trimmed all the way in. Any other setting is just wasting gas. I'm also going to guess that you either don't have trim tabs or are not using them. Either get some or use them. Drop the tabs all the way down and then pull them back up when you are on plane. The tabs will get that nose down and help produce the additional lift needed to help tip the boat over. Tunnel tabs will also help-even if they are set neutral. When the boat is planing out, the nose will tip up and the tab will dig in thus forcing it back down.

You are in the class of boat where it will never plane out well. Try to find a prop or method that will get you the good top end number and just be happy that it can get on plane.
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Old 06-23-2003, 11:15 PM
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Cord has it right pull the drive all the way in and push the gas to about 5500 and leave it the until it starts to plane out then you can back out a little. Most cats run a hi X prop close to or above the bottom of the boat good for top end bad for low speed bite.Larger diameter or more blades will help but put more stress on the drive three blades are faster most of the time try to borrow a prop before you buy it much cheaper if it doesn't work.
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Old 06-23-2003, 11:26 PM
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Unhappy problem is.............

I can't get the boat to 5500 rpm's without the motor staling.....it will sputter and stall with a gasp witht he load of trying to get to 5500 rpm's..and I know that can't be right.
 
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Old 06-24-2003, 08:56 AM
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It sounds like there is something else happening then. I can't imaging a prop/gear ratio being so far off to actually stall an engine.
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