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  #1   IP: 98.189.172.157
Old 04-29-2013, 06:52 PM
yeahjohn yeahjohn is offline
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Quick Carb Question.

Today is carburetor day I guess. So I am a carb slash fuel issue expert but for the last 6 months have been running great. Yesterday I experienced a issue that I am sure is a carb problem and I think it is the main jet or fuel delivery blockage.

Here is the issue: throttling up in forward coming into the harbor I pushed her up to 1500 rpm (high for me), she held there for one second then just dropped down to 1200 rpm, so I throttled down and then pushed it back up to 1400 and lived with my 4.7 knts without wanting to upset my engine in the windy channel. I am going to clean my carb and replace my water separator and polishing filter just for spring cleaning, but what caused this issue? Thanks.

John

And on a side note, thanks to Neil, I battled through my reversing gear assembly install and have the boat all back together and am back on the water!

Last edited by yeahjohn; 04-29-2013 at 07:54 PM.
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Old 04-29-2013, 07:18 PM
JOHN COOKSON JOHN COOKSON is offline
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Something around the prop\shaft????

TRUE GRIT
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  #3   IP: 24.224.152.244
Old 04-29-2013, 08:06 PM
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Smile

Good point John...could try reverse tied to the dock and see if some seaweed etc comes off the prop. Has happened to me. Last year it was a cable..

John,
For the time it takes you could do a carb cleaning anyway and change out filter and element is separator. Both are often overlooked and regular yearly maintenance goes a long long way.
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Old 04-30-2013, 02:30 AM
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ndutton ndutton is offline
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John,

You might consider drawing off some fuel and examining it in a glass container again. Now that you're using the boat the fuel is sloshing around in the tank and might be launching more residual krapola into the mix. More of the same.

If there's krud in the carb it came from somewhere.
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Old 04-30-2013, 08:50 AM
Dave Neptune Dave Neptune is offline
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Exclamation Preassure?

John, did you try the choke to see if it helped? Did you look at the plugs after the problem? If so how did they look?
I'd first check the filters and for proper fuel preassure at the carb. If you have a polishing filter cut it open and look inside for something clogging it up.
Remember if there is gunk in the carb it is also in the lines. AND if you have gunk in the polishing filter that could well be the restriction because it was doing it's job and is now restricting the fuel flow~~a gage would tell you this!!!!
A cheap preasure gage will eliminate a lot of guess work and aid in the diagnosis now and in any future issue.
If you find a restriction in the filter(s) replace them and try it again.
Cleaning the carb will possibly buy some time but the KRAP doing the damage needs to be managed.

Dave Neptune
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Old 04-30-2013, 09:47 AM
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edwardc edwardc is offline
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I used to have a similar problem when the engine wasn't fully warmed-up, although it was around 1100 vs 1500 rpm. If I didn't back-off when it happened, the engine would usually stall. Is your's an old-style carb? I believe they have a higher transition point from the idle circuit to the main.

Anyway, my problem turned out to be an idle mixture that was too rich, combined with insufficient advance on the timing. Once I got the mixture down to where it belonged (with the help of a fuel:air ratio gauge), and got the idle smoothed out by advancing the timing, the hesitation and flutter/stall completely went away.
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  #7   IP: 98.189.172.157
Old 04-30-2013, 06:36 PM
yeahjohn yeahjohn is offline
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Interesting edward. My mix is rich and my timing may need work. I was thinking a good tune up may be in order. After running for an hour today i couldn't even hit 1500 rpm... so maybe that mark was just to good for me either way.
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