5hp Briggs Will Only Run On Full Choke

bertsmobile1

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Check your fuel line for cracks as well. Spray carb cleaner around the carb to ensure it is sealed. My fuel line had an almost invisible crack allowing enough air in for surging, but did not leak. So check the whole fuel feed system for air intrusion.
Joe,
I understand you are elated that your problem has been resolved , but every problem is not a nail for your hammer to hit.
This mower has an internal fuel pump directly into a cup which acts as a float bowl so is fully internal .
 

CommandJ

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Apr 18, 2021
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So, I am not the best with carburetors and I am learning as I go. I had a few moments to look at things and was hoping someone might educate me on what I guess is the idle circuit? So I looked at the fuel pickup tube and the tube looks fine with no cracks. I am replacing the plastic piece that attaches to the fixed pressed in tube. But what I’m curious about is how the adjustment screw I have for idle operates. I attached some photos and put some arrows pointing to the particular hole I’m talking about. now, it may just be my eyes but when I remove the idle adjustment screw and look down at the base of the hole it looks like there is two small passages. One of the passages goes up to the welsh plug that I removed and you can see I put a small wire in it in one of my photos. Well on the opposite side it looks like there is a hole but nothing will go in. there Is a ball plug on the underside right where that hole is. i am guessing that is normal but I just don’t understand how the adjustment works if that hole doesn’t physically go anywhere. What am I adjusting, airflow Only and no fuel? I’m sorry for the stupid questions. Trying to learn as well as get this motor operating properly.

4F27B37A-157F-4A3F-B2BB-7D482C8C7AE0.jpegD939FF9F-1A82-43D2-BCF8-DA3AA62A5C7B.jpeg3FD138FC-5125-467C-855F-46159E98EA74.jpeg
 

Fish

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Yeah, that was a bit rough..
tankbriggs.jpeg
 

CommandJ

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Lol yeah it was in bad shape. I’ve replaced the tank. I just don’t know what might Of happened to the fixed jet with all the rust.
 

CommandJ

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Apr 18, 2021
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So I figured I would update everyone. Got the original carb working. No surging now. Ended up being the idle circuit. One of the small passages was blocked. Ended up having to remove one of the ball plugs to really clean it. The only thing I find tedious is setting the rpm. For the post part I have the max rpms set to is 3600. Occasionally it dips to 3540 or goes up to 3660. The idle was trick. From what I read it’s supposed to be set to 1750. I like the sound better when it’s in the upper 1800s or lower 1900s. 1860 to 1920.
 
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