Anyone else have this problem?

[fhiggenbottom]

After detecting the strong smell of gasoline in the garage where they're stored, I discovered that the KH-12-853-140-S Walbro carburetor on one of my Cub Cadet 1330 riding mowers (I have five now) had started flooding its vertical shaft Kohler 12.5 hp engine and crankcase with gasoline. I thoroughly cleaned the jets and carburetor bowl with carb cleaner and compressed air which resulted in no real improvement. Instead of trying to rebuild it decided to just replace it with a new carburetor. I chose a $15 Chinese manufactured carburetor from Amazon instead of buying a $200 + OEM Walbro carburetor and installed it.

No matter how carefully the fuel/air adjustment was tweaked on the carb it wouldn't allow the engine to start and run right. It only ran at full choke with the engine surging/hunting. I returned it and ordered two more Chinese carburetors for the Cub Cadet 1330 from eBay which were not adjustable. But upon installation one leaked from the fuel bowl and the other also leaked gasoline into the crankcase. Neither allowed the engine to run right.

I returned both of these Chinese carburetors and reinstalled the original OEM Walbro with a cutoff switch to prevent engine flooding. It ran perfectly with the Walbro, but the flooding problem remains. I wonder if anyone else has had success with using these Chinese knockoff carburetors on their machines and if so, what did I do wrong?

 

[mgonitzke]

You likely didn't do anything wrong. They are cheaply made and tend to be of poor quality, and don't have any quality control.

Why not get a KH-12-757-01 carb kit and rebuild the existing carb?

 

[dschwandt]

Shut the gas off when parking for any length of time.

 

[fhiggenbottom]

You likely didn't do anything wrong. They are cheaply made and tend to be of poor quality, and don't have any quality control.

Why not get a KH-12-757-01 carb kit and rebuild the existing carb?

I'm fairly mechanically inclined and quite DYI handy but I'm fearful of screwing up a carburetor rebuild and then not having any working carburetor to operate the engine! I've watched about every video on YouTube about rebuilding Walbro carbs (including always goofy Tridactyl). A a rebuild kit for my gravity fed carburetor is around $50 and on top of that if the rebuild goes badly or it doesn't fix the problem, I'm out the money and without any option to get the engine running except forking out almost as much money for a new Walbro carburetor as the mower is worth on the open market. The fuel cutoff valve works fine if I don't forget to shut it off after each use. Unless I want to keep trying Chinese carburetors until I get one that works, I guess I'll have to settle for that solution.

 

[abthomas]

I've used a few china carbs when I didn't have one to rebuild, sometimes you get lucky ,sometimes you don't ! I've rebuild some and ended up with the same issue , so I just shut the fuel valve when it's sitting !

 

[Doug Rusk]

I've never screwed anything up so bad I couldn't throw it away and start over. Or put another way you'll never fix it if you never try. New needle and seat will most likely cure your problem. Careful adjustment of float also. Be careful, take your time. Have a nice clean work area so if you drop anything you can find it. You will most likely be fine.

 

[mgonitzke]

These carbs are very simple to rebuild. If you are at all mechanically inclined it will not be an issue for you to do, and you're not going to screw it up such that it won't work. Take it apart, clean it all up with a spray can of carb cleaner, and replace the gaskets and needle in the new kit. Nothing to it.

I googled that carb kit part number; not sure where you are getting $50 from, it is available from a variety of sources for ~$16 or so.

 

[fhiggenbottom]

These carbs are very simple to rebuild. If you are at all mechanically inclined it will not be an issue for you to do, and you're not going to screw it up such that it won't work. Take it apart, clean it all up with a spray can of carb cleaner, and replace the gaskets and needle in the new kit. Nothing to it.

I googled that carb kit part number; not sure where you are getting $50 from, it is available from a variety of sources for ~$16 or so.

The OEM rebuild kit with a new brass insert in addition to the needle valve and seat is more expensive. https://www.amazon.com/Kohler-12-52...)+Part&qid=1683831732&sprefix=,aps,316&sr=8-2

 

[tkhoffman]

I'm fairly mechanically inclined and quite DYI handy but I'm fearful of screwing up a carburetor rebuild and then not having any working carburetor to operate the engine! I've watched about every video on YouTube about rebuilding Walbro carbs (including always goofy Tridactyl). A a rebuild kit for my gravity fed carburetor is around $50 and on top of that if the rebuild goes badly or it doesn't fix the problem, I'm out the money and without any option to get the engine running except forking out almost as much money for a new Walbro carburetor as the mower is worth on the open market. The fuel cutoff valve works fine if I don't forget to shut it off after each use. Unless I want to keep trying Chinese carburetors until I get one that works, I guess I'll have to settle for that solution.

Probably just a hardened rubber tip on the needle valve. I have that intermittent problem, I just put a Shut-off in line. It's become second nature to hop off the tractor, open hood and shut off the valve

 

[mgonitzke]

The OEM rebuild kit with a new brass insert in addition to the needle valve and seat is more expensive. https://www.amazon.com/Kohler-12-521-03-S-Original-Equipment-Manufacturer/dp/B00CSBQZZI/ref=sr_1_2?crid=PPZC6D874E1M&keywords=Kohler+12-521-04-S+Kit+Inlet+S+Genuine+Original+Equipment+Manufacturer+(OEM)+Part&qid=1683831732&sprefix=,aps,316&sr=8-2

Didn't know you could still get one that has the seat. That's the one to get then.

 

[MadMonkMort]

I'm fairly mechanically inclined and quite DYI handy but I'm fearful of screwing up a carburetor rebuild and then not having any working carburetor to operate the engine! I've watched about every video on YouTube about rebuilding Walbro carbs (including always goofy Tridactyl). A a rebuild kit for my gravity fed carburetor is around $50 and on top of that if the rebuild goes badly or it doesn't fix the problem, I'm out the money and without any option to get the engine running except forking out almost as much money for a new Walbro carburetor as the mower is worth on the open market. The fuel cutoff valve works fine if I don't forget to shut it off after each use. Unless I want to keep trying Chinese carburetors until I get one that works, I guess I'll have to settle for that solution.

Matt on the Diesel Creek YouTube channel has rebuilt several small engine carbs on his show, I'm sure he's done a Cub Cadet, because he collects them along with all sorts of other old construction equipment. He's got a line of about 15 Cubs sitting around that you catch a glimpse of occasionally. I don't know if you could search specifically for a CC rebuild on his channel, but he's resurrected at least one I can think of. Plus it's fun to watch him work and figure out problems like this.