18.5 HP Briggs

digr

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Runs not the best at full throttle but good enough ti get the job done, at idle it seems to run out of gas until the governor kicks in and keeps repeating. Is this carb adjustable?
 

ILENGINE

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You will need to help us out getting us the model, type and code from the engine so we know if this is a 33xxxxx series or the 38xxxxx series or the 42xxxxx series engines.
 

Bertrrr

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Not sure these new carbs can be adjusted other than idle speed , Probably need to pull it and clean it good , might have some debris in the bowl or jets
 

Forest#2

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If it's a Overhead valve type Briggs get the engine info from the top of a valve cover.
 

digr

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I will get the number after I get the lawn mowed, still have a acre left, I didn't want to monkey with it until I was done.
 

Forest#2

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I will get the number after I get the lawn mowed, still have a acre left, I didn't want to monkey with it until I was done.
You do not have to remove the valve cover to get the info, UNLESS some Bubba installed the cover upside down. If a twin Bfiggs it's usually on the top of the right side valve cover (as you are setting in the seat looking forward)
Be sure to get all correct when posting. Sometimes a 3 is a 8 etc due to weak stamping into the metal. After you get the ID model, type, code you can go to the computer and type the info in and add parts at the end in the search bar and if the info is not correct the computer will tell you to try again with correct info. this saves us a waste of time browsing with wrong info.
 

digr

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Model 31Q777
Type 0466E1
Code 050114ZD
 

Forest#2

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You will get some replies now that you have posted the ID info.

Here is a link to IPL parts list for your engine.
It came out with 3 different carbs, the Walbro which is NLA was the better one. Yours is most likely the Nikki.
If yours is a Nikki try to save it rather than using the cheap China clone replacement at $20 or less.
You can find lots of repair info on-line search for your carb. (once your know which one you have) assuming your is carb issues.
Here is one link as a starter that will show most all carbs except the Ruxing type.
https://outdoorpowerinfo.com/repairs/
 

digr

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I took the carb off and cleaned it now it won't run at hi speed , it floods I think it is the high speed jet that was laying on the carb when I lifted the float housing off. I assumed it went into the float housing with the O ring toward the bottom of the float housing, I will take it apart again and see if the jet flipped when I dropped it into the float housing.
 

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Forest#2

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That jet is going to need a NEW o ring. What you seen is a sign that the carb wants a kit. (might as well knuckle down and do such.
Here is some info for you to review. Also note that the rubber gasket ABOUT the emulsion tube MUST BE ingood shape and not leak. It will let gas in and appear as though the needle and seat is leaking when it does not seal.
You can find lots of info on line about how to remove, install kit etc using a Nikki one barrel carb. Keep a heads up and don't break the plastic on top of the carb throttle plate when removing or installing.

Here is some info



Nikki Briggs one Barrel carb rebuild tip, you tube.



This is the carb used on single cylinder Briggs engines in place of the Walbro LMT. The NLA Walbro LMT is the better user friendly carb.

You tube link

Nikki Carb Rebuild Single Cylinder Briggs - YouTube



Also see

https://outdoorpowerinfo.com/repairs/

Small Engine, Lawn Mower, Snowthrower Troubleshooting, Repairs and Safety (outdoorpowerinfo.com)
 
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