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We have had a recurring issue with a Scag 48 with a Kawasaki fs548v engine. Twice it has started to run rough and died. Gas was 3 or 4 inches up in the dipstick and fuel was leaking out of the muffler. Took carb apart and cleaned thinking needle was stuck. Did an oil change and it was fine for a week but has happened again. Compression is even on both cylinders it is only 70 psi but manual says minimum is 65 psi. Leaning on a new aftermarket carb. Was thinking possibly fuel pump. Is there a way to test with a vacuum pump?

Check the short pulse line to the fuel pump. If there is evidence of fuel in the tube, the diaphragm is ruptured. Otherwise replace the float valve. No need to replace the carburetor.

kenneth2 said:

We have had a recurring issue with a Scag 48 with a Kawasaki fs548v engine. Twice it has started to run rough and died. Gas was 3 or 4 inches up in the dipstick and fuel was leaking out of the muffler. Took carb apart and cleaned thinking needle was stuck. Did an oil change and it was fine for a week but has happened again. Compression is even on both cylinders it is only 70 psi but manual says minimum is 65 psi. Leaning on a new aftermarket carb. Was thinking possibly fuel pump. Is there a way to test with a vacuum pump?

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Remove carburetor and clean. Inspect and test needle and seat. Install fuel shut valve for added protection if desired. Could be as simple as some debris caught between needle and seat.

Thanks for reply’s, cleaned needle and seat. Thinking they may be old and dry. Aftermarket carb cheaper than factory needle valve, maybe I will swap parts. Also how do I delete a post. I posted same message twice.

If you can buy a carburetor for less than the cost of a float valve, $18, I would be leery.
Also, there is no FS548V engine. FS541V maybe?

There is no such fs548v. Please post the correct engine info.

Yes fs541v, sorry

kenneth2 said:

Leaning on a new aftermarket carb.

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Why? Clean the one you have first. Might need a new needle and seat if the cleaning doesn't help. I would put an inline fuel shutoff valve on her if it was mine.

kenneth2 said:

Was thinking possibly fuel pump.

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Why? You have more than enough fuel reaching the carb.

kenneth2 said:

Is there a way to test with a vacuum pump?

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Finger or vacuum gauge? Cigar or smoke machine?

Fix the carb issue before using the machine. Do a couple oil dumps. Oil is cheap, engines are not.

Yeah all set now. Carb is cleaned and all good for a week now

What was the fix action? Dirty carb?

Yeah dirty carb, all set now….

Yep dirty carb all set

Glad to hear she is running.

Does this have a good paper fuel filter on her? Good clamps on both sides? New fuel line from tank to carb?

Do you have an old fuel can with say maybe an open top? If so, get a new style spout. You can buy just a spout. Help keep trash and water out of your fuel. Once your can fills with debris, you pass it to your mower. Grass clippings, hornets, dirt dobbers, leaves, WATER and so on LOL. I feel they keep the fuel fresher as well. Below the picture is the Briggs spout. Don't get some other cheap POS from Scamazon or Fleabay.

Inline fuel shutoff valve? Install and use it or if you don't have one get one.