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troubleshooting: 4041/ac620

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Jed, Is it getting fuel to the carb.? If not, I'd guess fuel pump diaphragm. If it is getting fuel - then I'd try new plugs and then a new set of points. These CCKB's are pretty touchy on exact point gap (0.020") and timing. Hope you get it figured out quickly. Jeff

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I found out how critical the timing is on the Onan CCKB last spring. My 720 exhibited the same symptoms as your tractor. Also be aware of the fuel screw setting (bottom of the carb bowl). One and one-half to two turns out is plenty, and it's very touchy! The fuel pump is a weak link, but after rebuilding mine (about $25 for the rebuild kit), I've had three years with no problems. Good luck with your machine!

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It died in the middle of the field while mowing. It had been running strong for an hour, but then seemed to bog down a few times, and finally crapped out altogether. It turns over, seems to have spark, but won't fire. Checked points and fuel filter. There is gas in the tank. I blew air back through the line into the tank to make sure the line isn't blocked. Any ideas? Thanks in advance for your help.

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Same thing happened to me just yesterday, I was out with the 620 with the loader piling up leaves and it just started to miss and then it just quit. Took me 4 hrs. to get it back runing. back and forth to the shop 50 times. finally found the problem,the condensor crapped out, man what a time taking the tractor apart out in the field, now I really appreciate the shop!!! Aren't these old girls fun!!!! Floydster

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