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Discussion Starter · #1 · (Edited)
I went out Saturday to try my 97 Blue Wave with an 96 Evinrude 115 which hasnt been used in a while....I couldnt get the engine above 4800 to 5000 RPM. I recently purchased this boat.....this was my first time to try it out.....It has a 4 blade uncupped prop. It does plane out but it just seems it should have more punch on the engine. I will change the spark plugs today.....I flushed out the old gasoline which had stabilizer according to the guy i purchased from before I tried it. How do I know if it needs a carb kit...or just replace spark plugs or both? turns on and idles just fine...
 

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Depending on the exact model, you should be able to get a minimum of 5500 rpms at wide open throttle. You could actually be putting an unecessary load (strain) on that motor at such a low rpm.
 

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I have a 115 e-tec and at WOT the highest rpm i can get is between 5200-5400. I have to do some trimming to get the rpms at 5400. I usually cruze around 4500-4600 rpm which is about 32 mph.
 

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Okay, not really sure what you asking. The motor with the correct prop needs to be able to reach or come very close to the maximum rpms for the motor, period, whether you ever intend to run it that way for long or not. If you can't even get to 5000 then you are lugging the motor down somewhat. It would kind of be like driving a car 30 mph in 5th gear. Yeah, you could do it, but it probably wouldn't be good for the car.

Cruising rpm. All depends on the particular motor and boat, but I would say most rigs get maximum mpg somewhere between 4000 and 4500 rpm.
 

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Need less pitch in prob to increase that rpm. (Unless you think you have engine issues)
 

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the motor should turn about 5800 wide open and timmed out. number 1 question are you timmed out? number2 what pitch prob are you running? these need to be answered before going to carb problem. hope this helps.
 

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dont do anything - if it works leave it alone ... if the boat does not shake at ideal or does not have statring problem,m leave it alone .. 4 blades slow the rpm do to their grippong power , you get a better hole shot but move slower. a prop that is near surface will spin faster than a prop fully submerged .
 

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Huh? It does not matter if you are running a 3, 4, or 5 blade prop. It should be pitched and cupped so that the engine turns between 5500-6000 rpm wide open.
 

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I just purchased a new used boat and it was turning 6100 rpms wot when I first got it. I had the prop reworked by Baumann Props and am now turning 5400 wot.

If you change the spark plugs, carb job, flush motor and it still runs at too low of an rpm (less than 5000) but runs good, I would suggest talking with a prop guy about the size/pitch of the prop.
 

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I carry a Gun, cause I can!
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Discussion Starter · #12 ·
prop pitch

OK, so what is the ideal pitch on a 4 blade prop to get 34 to 38 mph. I used to have a an 88 spl with an 18' sprint shallow sport with a 17 pitch 3 blade prop....it ran around 35 to 37 mph at around 5400 rpm. Now I have the 189 Super T Bluewave with the 115 evenrude.
if everyone will let me know the

1. Pitch
2. # of blades
3. RPM
4. MPH
5. Type of boat, length & weight
6. Engine horse power

maybe we can iron this out once and for all with all the setups everyone has...
 

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If you can only get 4800-5000 with your current prop then as a general rule you need to drop an inch of pitch for about evey 150-200 rpms you want to add to reach redline rpm.. This is providing that the type of prop and the diameter stay the same.
 

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Discussion Starter · #15 ·
RPM on Evinrude 115

Someone was telling me today that these engines have a governor set so they dont go over 5000 RPM......how true is that? Anyone know?
 

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texasranger225 said:
Someone was telling me today that these engines have a governor set so they dont go over 5000 RPM......how true is that? Anyone know?
Don't know about that. If they do, it wouldn't be set at 5,000. If it's not an Intruder, I believe the max recommended rpm is 5,500 and the minimum at WOT is 4,500 rpm. A lot of guys prop them to run around 5,800 rpm at wot.
 

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Question

What did the previous owner say it turned (rpm's) when you bought it or before it was sitting up? If it use to turn up before, could have a carb problem or missing on one cylinder. If that's how it always ran, maybe too big of a prop.

Good Luck
 

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If you are turning at least 5500 wot then it sounds like you are trying to turn too much prop. I had the same problem went to Baumans told them the rpms at wot and they put right at 5700 wot and I actually gained 4 mph due to not lugging the engine with a lower pitched prop and got a better hole shot best of both worlds from where I started at.
 

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Discussion Starter · #20 ·
My 115 Evinrude

Mechanic came by to look at my engine. He looked at the engine, checked the compression which by the way is 130 on each piston. He noticed the little plastic looking tube that fits on the timing mechanism was gone......so that was replaced. I had him replace the water pump....he told me it was still running the original water pump......which he could tell because of the o-ring it comes with at the bottom of the impeller. So.....anyway...I will get out to the Rio Grande River since it is closer then South Padre Island, soon and will let yall know if the replacing of the spark plugs and adding the missing timing little plastic looking tubes thingies.... fixed the problem.

yall have a great day and always C.T.R. (Choose the right)

Roland
 
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