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 Pitch or rich 
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Joined: Thu Jan 17, 2019 10:15 am
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Post Pitch or rich
So I think I have my longtail running fairly decent I just need to know y'all thoughts on this video I believe I'm either running
a little rich on the bottom in making it drag or possibly a little lean because it's starving for fuel. And on the top end I'm pushing almost 4,000 RPMs which makes me believe that I am running too low of a pitch mi prop. With me my wife and my daughter which is 6 years old I am still getting around 3800 RPMs watch the video and tell me what y'all think.[YouTube] https://youtu.be/XOe5aCeVxL8[/youtube]


Sun Mar 24, 2019 10:55 pm
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Post Re: Pitch or rich
Running between 20 and 22 depending on the way this, what was, a 20hp kohler feels.


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Sun Mar 24, 2019 11:00 pm
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Post Re: Pitch or rich
Sounds and looks like it runs pretty good on step. If you add more pitch, you will lose holeshot but may gain a bit on the top end. Prop wise, I would probably leave it alone so you don’t lose the holeshot it looks like you have. That is, unless running 4K is wayyyy too much for a 20 kohler, because I don’t know what the recommended rpms at wot are for that motor


Mon Mar 25, 2019 8:27 am
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Post Re: Pitch or rich
Nah 4k isn't way to high. Just out of my powerband with stock cam. Seems like a waste of potential power. Didn't sound like it was bogging at little in acceleration?


Wed Mar 27, 2019 4:07 am
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Post Re: Pitch or rich
I didn’t think it did, but sometimes it’s hard to tell with a video. To me, looks like it runs pretty good. If you want to get the prop dialed in, just send it to baggy


Wed Mar 27, 2019 4:30 am
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Joined: Mon Dec 31, 2012 11:07 pm
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Location: West Monroe, LA
Post Re: Pitch or rich
Dont send a long tail prop for a 20hp to get worked. Waste of money. What you have is running fine, and there are 3 different brands of longtail props that all perform slightly different for same pitch and size that you can try as time goes on. 20mph+ is fine for a 20hp, as is the hole shot. Make sure the mixture screw(s) are adjusted correctly on the carb, and maybe do a throttle chop to check plug color at wot, but it's running fairly well, and all engines get out of the meat of the powerband at upper rpms. It's not a bad thing. Dont prop it or set the gov to drop from 4k. You'll be limiting yourself.

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Wed Mar 27, 2019 6:46 am
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Post Re: Pitch or rich
I'm more concerned about that mid rpm range stutter. Is that a sign of rich or lean? And I'm not running a governor. My prop pitch is my governor. =)


Sun Mar 31, 2019 3:04 am
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Location: West Monroe, LA
Post Re: Pitch or rich
You removed the gov?

Typically a stutter/hesitation in the mid range is too much fuel while the air flow velocity catches up, but without watching it run, that's not something we can diagnose. In your video I didn't notice it.

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Sun Mar 31, 2019 6:30 am
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Post Re: Pitch or rich
Yes it removed gov completely. But I think I have found out the problem. I took my outboard off the he bat and slapped the longtail on. After I fired her up, to make sure everything was in order I started hearing #2 cylinder exahust sound like it's in a 5 gallon bucket of water. So I pulled the plug with it still running and it didn't change RPMs. So I put my spark tester on and off coarse it couldn't be a coil, that would be easy. It was getting great fire. So I'mma run a leak down test here in a little bit. I got a feeling the exahust valve seat is toast. I pulled valve cover off. and everything is moving as should so shouldn't be that cam.


Mon Apr 01, 2019 4:12 am
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Post Re: Pitch or rich
I think I got it figured out! I don't think this big gap us supposed to be there. =\ time to bust the case open.


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Mon Apr 01, 2019 2:14 pm
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