Briggs 21HP mower shutting down - Weingartz Expert Advice
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Briggs 21HP mower shutting down

Q. My 04 Briggs 21 HP started up fine. I made several passes through the yard and the unit shut down. I found that the fuel switch and 1 coil shorted out from mice, so I replaced coil and fuel switch along with the wires. Now the unit starts and floods out. I can see fuel in the intake, so I shut unit down and the engine speeds up and dies since fuel switch is working. I replaced seals and float body along with new needle valve, and with the bowl off I can see fuel turn on and off by finger movement of float but unit will flood out when started. I shook carb and can hear the float moving. Then I removed float and tested it on a clear bowl and float will move in fuel. Do you have any idea why it floods out?

A. While it is difficult to diagnose a carburetor problem on your Briggs 21 HP lawn mower without seeing it there are a few things you can check for:

  1. Is there any fluid inside of the float? If the float is cracked, fluid may seep inside.
  2. Check the seat, is the float is sitting correctly?
  3. Is there any debris in the float bowl? Sediment can get sucked up into the carburetor causing blockage.
  4. Check the atmospheric vent for blockage If these do not solve the flooding, you might want to consider a new carburetor for your Briggs lawn mower.

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2 thoughts on “Briggs 21HP mower shutting down”

  1. I have 2001 honda generator and it won’t crank Gas is going to the carburator but not to the spark plug I am hoping you can tell me what is wrong or what part I may need Thank you very much for any advice you can give

    Reply
    • The issue with your Honda generator is likely the carburetor. I would suggest that you clean the carburetor and possibly re-build with the needle valve and bowl gasket. It is also possible that you may need a fuel solenoid, depending on the model of your Hnda generator. Give us a call (855-669-7278) with your model number and we can help you locate the part(s) you may need.

      Reply

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