Small Engines (Lawn Mowers, etc.)/Carb flooding


QUESTION: This is a ten year old Craftsman with a Kohler engine model # cv490s . I removed the air filter and saw gas in the bottom. Took out the spark plug and gas just gushed out of the hole. I tested the solenoid and it was working .The float looked ok, didn't seem to be sticking.  So I replaced the needle, it started but was still blowing a little gas out the exhaust. Having a brass seat I wasn't sure if it could be replaced. So I replaced the rubber tip on the solenoid. That seemed to work, started right up with nothing blowing out of the exhaust . I mowed the front, two days later it's doing the same thing. Blowing gas or something out the exhaust. So I'am lost, not sure what the problem is. Thank you for help!

ANSWER: Is the address below the service manual for your engine?

What is the full engine model, spec and serial number?

I need the engine info to look up your carb but based on some research you carb probably has a replacable inlet needle seat.

Let me know all the info so I can look up your carb.


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QUESTION: That could be the manual for mine, looks the same.

Model no. CV 490S
Spec no. 27505
Displ (cc) 490
Ser. 3033904563

Family- YKHXS4902GB

ANSWER: Yep, this is the address to your manual:

Fuel Inlet Seat Removal
The fuel inlet seat is pressed into the carburetor body, do not attempt to remove it. If necessary, clean it in place with aerosol carburetor cleaner.

Based on the Service Manual info you can not replace the all you can do is replace the inlet needle.  Does the inlet needle have a rubber tip?


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QUESTION: Yes it has a rubber tip.

I would replace the needle as the viton (rubber) can become brittle and cause leaking.  FYSA, we are recently seeing a lot of fuel issues with lines and all other rubber/viton parts.  Many articles have recently emerged as well indicating the ethanol fuel is causing increase deterioration of rubber parts in outdoor power equipment to include boats, ATVs, motorcycles as their parts are not designed to work with the increase ethanol fuel blends.

I would also recommend buying the lowest % of ethanol blended fuel and use an ethanol fuel treatment in the fuel.


Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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