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Mesa AZ
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Discussion Starter #1
I have a daytona with a 250 johnson with a 15x21 hills prop and the boat only spins 5100 rpm and the boat runs about 50mph . I know it will run faster what prop should i go to . im told this motor should spin 8000 rpm . what prop would be good
 

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Depending on the year of the motor, it might go as high as 6700, but not 8000. Definitely have too much prop right now if you're only at 5100rpm. Probably too much diameter too. I'd be looking at a 14.5" x something. I'd think your boat should pull a 26 without problem.

As Jordy said, call Kevin. He'll steer ya right.
 

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two strokes is enough
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Depending on the year of the motor, it might go as high as 6700, but not 8000. Definitely have too much prop right now if you're only at 5100rpm. Probably too much diameter too. I'd be looking at a 14.5" x something. I'd think your boat should pull a 26 without problem.

As Jordy said, call Kevin. He'll steer ya right.

yah he could run a 26 but its a through hub exhaust that will make it grab alot more and not let you spin that motor quite as fast. like keith said try and find a 14.5X 20 or 21 but also give kevin a call hes a great guy and very knowledgable
 

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Ron hills props are no where close to what he says they are. I have had some experience with them and ever could get any of them to run like he says they should. I would look for a 14.5 X 24-26 chopper II. I would think with a 26 you should be running close to 80 at WOT.
 

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I'm guessing that's a 235 given the year. IIRC, you want to turn those around 5800-6000, so you're a bit off the mark. Again, call Kevin. He knows the motor/rpm range and the props.
 

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Saguaro on Sunday AM

Hallettss,

Dick and I will be at Saguaro early Sunday morning for a couple of hours. usually 7 - 10sh. water permitting, it'll be an all Merc day for us. We'll be running my PowerCat and the blue Hydro, it needs really good water or it goes back on the trailer.

If you'd like, your more than welcome try one of my 24" choppers, I run twins. It would atleast let you know if you can spin it and see if the boat likes it, they are pretty easy to find and affordable. You should in my IMO be able to spin that Hill prop faster, perhaps it was suppose to be stamped 15 X 27?

We've got a buddy with a similar hull to the daytona with a 200 OMC, spins a 24 chopper to 6200.

If your motor can't do it then we suspect there's something wrong, that motor should make plenty enough power. Have you checked the plugs or compression?

Anyways let me know if your interested, like I said your more than welcome to try it, if that's a little to early we'd be willing to wait around a bit if we know your coming..

Best regards,
Jeff

Cave, you gonna be up there Sunday AM?
 

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Mesa AZ
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Discussion Starter #13
That would be great if i could try it i will be there around 8:30 . motor runs good dont think there is a motor prob .I will check the comp in the am what should it be.
 

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Sounds like a plan,

I honestly don't know what the compression should be, I know the OMC's tend to be lower than the Merc's, (low 100's I believe, we don't run any V6's, to new:)sphss) Can you find a model or SN# anywhere? There should be an external tag somewhere on or around the clamp bracket.

I know a guy that probably has a manual, I can try to find out. Perhaps STV Keith or Greg Moss would know. Guy's you out there?

Jeff
 

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compression #s

A quick check online looks like it could be as low as 90 to 120sh, depending on the model heads it came with. Assuming early 80's 235..

Even #s across all 6 would be good of course..

SN# and Model#s are critical with these things, (anything outboard) give it a good looking over, hopefully you can find the tag (assuming its still there)

Jeff
 

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should be a tag on the swivel bracket. If not there then if it is a cross flow motor it will have a freeze plug on the block above the #2 cylinder. If it's a looper motor it will have a freeze plug in between the cylinder banks in the exhaust water jacket about 3 inches from the top of the block. when you pull the cowl off and looking at the motor from behind it should be right in front of your face.
 

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Hallettss,

Dick and I will be at Saguaro early Sunday morning for a couple of hours. usually 7 - 10sh. water permitting, it'll be an all Merc day for us. We'll be running my PowerCat and the blue Hydro, it needs really good water or it goes back on the trailer.

If you'd like, your more than welcome try one of my 24" choppers, I run twins. It would atleast let you know if you can spin it and see if the boat likes it, they are pretty easy to find and affordable. You should in my IMO be able to spin that Hill prop faster, perhaps it was suppose to be stamped 15 X 27?

We've got a buddy with a similar hull to the daytona with a 200 OMC, spins a 24 chopper to 6200.

If your motor can't do it then we suspect there's something wrong, that motor should make plenty enough power. Have you checked the plugs or compression?

Anyways let me know if your interested, like I said your more than welcome to try it, if that's a little to early we'd be willing to wait around a bit if we know your coming..

Best regards,
Jeff

Cave, you gonna be up there Sunday AM?
Most likely I will be there Jeff.
 
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