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7040 erratic rpms?
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nickia View Drop Down
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Joined: 11 Sep 2009
Location: alden iowa
Points: 801 		Post Options Post Options   Thanks (0) Thanks(0)   Quote nickia Quote  Post ReplyReply Direct Link To This Post Topic: 7040 erratic rpms?
    Posted: 12 Jul 2026 at 9:39pm
I have a 7040. Mowing 3/4 throttle and all of a sudden my Rpms jump maybe 2/300 rpms for no reason. Eventually the rpms will work it's self down but when it acts up it's like engaging a turbo boost. I've changed my fuel filter once dirt black fluid came out. Running trk stop bio fuel blend. Would you try another filter change? Or do I need pump service work?
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DrAllis View Drop Down
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Joined: 12 Sep 2009
Points: 23484 		Post Options Post Options   Thanks (0) Thanks(0)   Quote DrAllis Quote  Post ReplyReply Direct Link To This Post Posted: 12 Jul 2026 at 9:46pm
Sounds like dirty/bad fuel. Bio blend prob not good. Remove filter and blow back into the tank and try another filter.
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WF owner View Drop Down
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Joined: 12 May 2013
Location: Bombay NY
Points: 5303 		Post Options Post Options   Thanks (0) Thanks(0)   Quote WF owner Quote  Post ReplyReply Direct Link To This Post Posted: 13 Jul 2026 at 5:34am
...or possibly a little air getting into the fuel system.
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injpumpEd View Drop Down
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Joined: 13 Sep 2009
Location: Walnut IL
Points: 5273 		Post Options Post Options   Thanks (0) Thanks(0)   Quote injpumpEd Quote  Post ReplyReply Direct Link To This Post Posted: 13 Jul 2026 at 8:45am
Fuel restriction, or air leak on inlet side of fuel system. With running bio you may want to plan for a pump service in the off season, provided it makes it though the busy season. 
210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers!
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SteveM C/IL View Drop Down
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Joined: 12 Sep 2009
Location: Shelbyville IL
Points: 9196 		Post Options Post Options   Thanks (0) Thanks(0)   Quote SteveM C/IL Quote  Post ReplyReply Direct Link To This Post Posted: 13 Jul 2026 at 8:51am
My opinion only....if running hard and constant bio is ok for less cost but something that sets alot not so much. Some BTO's run bio during spring and fall but switch back to real fuel before fall work is done to have systems rid of bio. Cheaper isn't cheaper.
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