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Elated Technician
Elated Technician, ASE Advanced Master Technician
Category: Car
Satisfied Customers: 486
Experience:  16 yrs exp, Auto/Diesel Associates degree, ASE Master w/ Advanced cert, Saab Master and BMW level 4
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run fine..vacuum..fuel just quits coming to the carb.

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I have a 17 hp Craftsman 42" mower that will start and run fine but after about 30 minutes it appears some sort of vacuum is building some where in the fuel line. The fuel just quits coming to the carb. When I sit there and tap the fuel line and shake it, it will start flowing again after a couple minutes. Maybe just a coincidence that I shake it and it flows again. It will then continue to do this about every 5 min. The tank is clean and the filter is good. What gives? I have also pulled the cap off to make sure it is venting and that doesn't help either.

Hello Jeremy,

It sounds like you have done a lot of good diagnostic work so far. My thoughts lead me to the fuel line itself. I have seen in the past where it will deteriorate from the inside and cause the flow to stop. Since you have checked the tank and removed the fuel cap, I think that is the only remaining link.

Let me know what you find,

Customer: replied 9 years ago.
Reply to Elated Technician's Post: Thanks for the response. Well the mower is only 5 years old so I wouldn't think the fuel lines would be deteriorated yet but I will replace them. Do you suppose anything in the carb like the float sticking closed might also be the culprit.

Hello Jeremy,

That is a possibility. I was under the impression you had removed the fuel line and found the fuel was not coming out. If the hoses to the carb are accessible, I would remove them and check if the fuel flows when it stalls. If the fuel flow is fine the floats would certainly be a good next step. Possibly some tarnish has gummed up the float or a passage and only shows up when it is hot.


Customer: replied 9 years ago.
Thanks for the info, for some reason since I didn't accept your answer right away it won't seem to let me accept it now so you will get paid. I'm new to this but I will get it figured out so you get paid. Thanks again, I will let you know what I find.


I believe I have to select final answer on my end. Thanks for choosing Just answers and good luck with the mower.



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