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Old 07 August 2019, 14:46   #1
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Suzuki 140df advice

Hi

I have an 2007 XS600 running a Suzuki 140df which seems to be down on engine RPM.

At WOT I’m hitting around 4500RPM trimmed out. Engine revs to around 3800 RPM and then picks up to 4500 RPM when on the plane.

The boat is coded and therefore, carrying a lot of kit, 8 man life raft, two 8kg anchors and chain etc. Hitting these RPM 4 up with around 50l of fuel.

Running a 3x14x21 prop. Do you think I’m over propped or just heavy?!
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Old 07 August 2019, 14:49   #2
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Way over propped. Iím running a 4x13.5x19 on a heavy 545 & just touching 6k RPM with 2 up.
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Old 07 August 2019, 15:39   #3
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I ran a 3x14x19 on that engine and it worked perfectly
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Old 07 August 2019, 15:59   #4
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Quote:
Originally Posted by xpertski View Post
I ran a 3x14x19 on that engine and it worked perfectly


On which boat & what load though??
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Old 07 August 2019, 18:46   #5
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Over propped for sure, 17 pitch would be closer to the mark or possibly 15.
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Old 08 August 2019, 04:51   #6
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Does the boat live afloat?
Is the bottom clean?
Might there be any water below the floor.

21" sounds too high to me. Is this the propeller that the boat came with? Has performance deteriorated over time?
Is the boat new to you?
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Old 08 August 2019, 06:36   #7
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On which boat & what load though??


Humber Ocean Pro 6.3m. 70litres fuel, usually 2-4ppl aboard. With 2 ppl I got anywhere around 36-38knots and with a full boat of 6ppl got around 33knots
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Old 08 August 2019, 06:41   #8
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Quote:
Originally Posted by xpertski View Post
Humber Ocean Pro 6.3m. 70litres fuel, usually 2-4ppl aboard. With 2 ppl I got anywhere around 36-38knots and with a full boat of 6ppl got around 33knots


What was the holeshot like with 6 up?
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Old 08 August 2019, 11:24   #9
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Chris, I'd reckon over propped. I have various props for that engine in Poole. I use a 17" prop when loaded up with diving kit etc. If you're local you're welcome to borrow a smaller prop see if it helps
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Old 08 August 2019, 15:56   #10
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What was the holeshot like with 6 up?


It was ok but no fireworks
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