3 carbs in a row leaking bad

Pigletrma

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My mower has a Kohler sv600 engine. IT started leaking gas out the air filter even when key is off . So I bought a cheap replacement off amazon. Same thing. So I bought a genuine Kohler (Walbro?) . Same thing! Seems to me like float is not shutting off gas - but on all three??? Any advice greatly appreciated!
 

Scrubcadet10

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I would suspect trash in the fuel lines, flows to the carb and hangs the needle and float open. I would replace the fuel line and make sure the tank is clean.
 

Pigletrma

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I would suspect trash in the fuel lines, flows to the carb and hangs the needle and float open. I would replace the fuel line and make sure the tank is clean.
Thank you. When will I ever learn the importance of clean fuel!!??!!
 

StarTech

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This where I pressure test a carburetor before installation. If passes the test an problems occur I too suspect fuel line contamination. I currently working on MTD mower where it sat a few years. I would never suspected saw dust to be clogging the fuel line.

And yes old fuel lines can cause problem too as rubber flakes off and jam the needle valve open.
 

Pigletrma

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This where I pressure test a carburetor before installation. If passes the test an problems occur I too suspect fuel line contamination. I currently working on MTD mower where it sat a few years. I would never suspected saw dust to be clogging the fuel line.

And yes old fuel lines can cause problem too as rubber flakes off and jam the needle valve open.
Thank you!
 

Pigletrma

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OK, following advice here, I drained my tank, and got it absolutely clean. I cahnged my fuel lines and put in a new filter. Dis-assembled the carb, float and needle. blew out and got all spotlessly cleaned. put it all back together. poured in clean gas, through a filter jsut to be sure. All started leaking again instantly! Im going out of my mind!!!
 

Pigletrma

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Thank you!
This where I pressure test a carburetor before installation. If passes the test an problems occur I too suspect fuel line contamination. I currently working on MTD mower where it sat a few years. I would never suspected saw dust to be clogging the fuel line.

And yes old fuel lines can cause problem too as rubber flakes off and jam the needle valve open.
Well, changed fuel lines, cleaned tank and carb. installed a shut uff valve and filter. hooked it up. Still leaking like crazy :(
 

Pigletrma

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Thank you for the links. Off the machine, with air, they hold pressure. Back on the machine with fuel, inlet needle leaks. If I rock the machine, it will sometimes get that float moving and it will stop leaking. Same for all three carbs?!?
 

slomo

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Thank you for the links. Off the machine, with air, they hold pressure. Back on the machine with fuel, inlet needle leaks. If I rock the machine, it will sometimes get that float moving and it will stop leaking. Same for all three carbs?!?
Which tells you what? You have a faulty needle and seat.

Also you need to test at 7psi for around 30 minutes with the needle WET. Shoot some PB Blaster on the needle while testing.

These work just like toilets do.
 
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