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Old 27-12-2012, 05:53 PM   #1
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Merc 2.4 carb

Hi guys can anyone tell me what my std 200 2.4 should rev to my ring only seems to pull around to about 5300-5500 with a 21 on it runs 66-68mph
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Old 27-12-2012, 06:01 PM   #2
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Hi guys can anyone tell me what my std 200 2.4 should rev to my ring only seems to pull around to about 5300-5500 with a 21 on it runs 66-68mph
Something is adrift !! Its either revving more than you think, Slower than you think, Prop bigger or you have a really high gear ratio.

Assuming 1.86:1 gear ratio
21" Laser type prop calc as 23"
Revs @ 5800
Speed 67mph less than 1% slip
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Old 27-12-2012, 06:08 PM   #3
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I no scotty boy worked it out too something ain't rite props a 23 re stamped 21 so I asume it's been worked most I have ever seen it rev to is 5500 and that made 68mph.engine seems to pull really well so maybe it's not std? What sort of revs a std engine make you think?
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Old 27-12-2012, 06:11 PM   #4
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What Gear Ratio ?
What type of Prop ?
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Old 27-12-2012, 06:13 PM   #5
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What Gear Ratio ?
What type of Prop ?
Not shore on the gearbox looks std props a laser
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Old 28-12-2012, 01:44 AM   #6
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Seems pretty good for a standard 2.4 200, how are you monitoring your speed? GPS?
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Old 28-12-2012, 10:22 AM   #7
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Seems pretty good for a standard 2.4 200, how are you monitoring your speed? GPS?
I no seems to pull really well! Yeah using a GPS. What should a std 2.4 rev too??
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Old 29-12-2012, 02:10 PM   #8
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Not a good idea to rev past 6k with standard 40amp electrics
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Old 29-12-2012, 08:29 PM   #9
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Not a good idea to rev past 6k with standard 40amp electrics
Can't get it to rev past 5500 any idea what a std 2.4 200 showed rev too?
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Old 29-12-2012, 08:39 PM   #10
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revs

should rev to 6000/6200,try a smaller pitch prop and if the revs dont go up theres something on the engine holding back the revs
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Old 29-12-2012, 10:49 PM   #11
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should rev to 6000/6200,try a smaller pitch prop and if the revs dont go up theres something on the engine holding back the revs
What do you think would hold it back? I have a second rev counter I may try just to make shore that's not at fault miss leading what the revs really are?
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Old 30-12-2012, 04:52 PM   #12
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Std rev 200 2.4 5300/5800
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Old 30-12-2012, 07:33 PM   #13
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How high is your motor set? Good compression on all 6? Could just be that you've reached the limit of your set up...
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Old 30-12-2012, 07:53 PM   #14
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Assuming the data is correct, then the prop is too big or gear ratio is too high !
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Old 30-12-2012, 10:28 PM   #15
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How high is your motor set? Good compression on all 6? Could just be that you've reached the limit of your set up...
Never done a compression check so not shore engine is really strong so may not be std used to be a x ski race boat
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Old 30-12-2012, 10:30 PM   #16
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Assuming the data is correct, then the prop is too big or gear ratio is too high !
I have a 24 4 blade trophie prop I want to try when the weather gets better. Don't think the gearbox has been messed around all look un touched
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Old 31-12-2012, 12:58 PM   #17
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I'd try the other rev counter before you change your prop to see if its faulty also how high are you running your engine?
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Old 31-12-2012, 05:08 PM   #18
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Engines just sat hard down on the transom may hack it up a hole or too that should help the revs up ay?
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Old 31-12-2012, 05:11 PM   #19
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That depends how high the transom is ??
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Old 31-12-2012, 07:18 PM   #20
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Make sure you still get good water pressure if you dont have transom pickups or a low water pickup gearbox
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