John Deere lawn mower won't stay running (100 SERIES)

I tried to recreate the problem, and run the mower out of fuel again to see if it would do the same thing again. I could not get the mower to do what it did the day I could not keep it running. I think all my problem was that it lost suction or got air in the fuel line. Maybe my fuel pump is starting to go bad. There are a lot of good answers and things to check in the comments thank you all for trying to help. I'm sure these answers will help someone else out. If you leave anymore comments on what to check try to explain how to do it so that it might help someone else out. Thank you again and God bless

Loved the whoop and hollar when your mower started! I make that same sound every single time my mower starts! Thanks for the tips!

My z540 would start and run for a few minutes and then sputter and stop. I could get it to restart and it would go for another few minutes and stop. I took the top cover moding off and detached both lines out of the fuel tank and blew the lines out. I then put it all back together and it started right up and never stop or sputtered like it did before. This video definitely helped me resolve my issues. Thank you!

Thanks mate did exactly what you said and now it works like a dream

Cleaning hole in gas cap worked for me! I have an older 125 automatic without vapor recovery. It started the season fine even with old gas and cold weather but then started randomly dying over the last two weeks, sometimes after 30 minutes when completely warm, other times within a minute of starting cold. I drained old gas, blew up through hose to tank, put in fresh gas, replaced fuel filter, plugs, oil change. Then I saw other comments in this post, knocked the dirt out of the tiny center hole in the gas cap and blew through it (also not tightening the cap super tight) and it has been starting and running fine for a couple of days. Surprising that such a tiny bit of dirt could impede the flow of gas and the suction of the fuel pump would not pull it through...maybe the fuel pump is on the way out but so far, so good for me and I would suggest anyone having similar problems try this easy step first.

Thanks for the great video! So I think your question was - "What is the return line to the tank". It looks like it is part of some kind of EVAP system to return gas fumes back to the tank for reuse. It's all emission control stuff that is part of a closed loop system. Blowing out the lines caused it to start functioning properly again..

Yep! You saved me, brother! THANK YOU!!!

Glad I saw this… Engine started surging shortly after I did a tune-up. Ran great for 10 minutes, then started surging and got worse as time went on. Even stared back-firing at low idle. I did what everyone else did… replaced fuel pump, inspected gas tank for water, etc. but just remembered when installing fuel filter, not much gas came from the line to the full tank. I should have investigated that, but I was so focused on other things, like maybe I missed something on the tune-up that I dismissed it and moved on. After seeing this it makes total sense. Tractor is 9 years old now and thinking the lines are breaking down. Gonna revisit tomorrow and try your method. Thank you.

I have had this problem with my John Deere since I bought it. It makes my crazy!! Will try your method now. Wish me luck!

Had same situation, I replaced everything cap ,filters, plugs,, cleaned carb flushed tank.. It worked an hour them dying and back to not starting. Finally gave up took to highly-rated J D dealer charged me $200 after mowing 10 minutes it stopped. Dealer took it back after having it 2 weeks and admitting they were puzzled they discovered the fuel lines were rotting from the inside and small particles were going thru the fuel line. Mower is 12 years old. After that 2 years no problems.

Super helpful. I’ll try that and possibly replace that air line. Mine surges below full throttle. Just disassembled the carb and it was clean as a whistle.

THANK YOU!! You just saved me a ton of money sending it to the shop!!

This worked perfect for me! thanks for your help! It has not run this good in years!!

I greatly appreciate the video and you getting this thread going. I had the exact same issue, pulled the line for the fuel pump- (out to carb), cranked it a few times, had great fuel flow, put it back together and fixed. I'm thinking air or a minor obstruction somewhere in the fuel lines. Thanks again!

I had EXACTLY the same problem. After watching the video and reading most of the comments below here is how I fixed the problem. I removed the gas cap and started the mower. I let the mower run for about two minutes. While the lawn mower was running I replaced the gas cap. That's all I had to do.

Also check the ignition wire from the key switch. If the wire is rubbing or vibrating on the steering shaft (rod) the insulation may wear and cause an intermittent ground short, which will cause the engine to stop. That happened on my LA 115. Fixed it by wrapping electrical tape around the wire where it was rubbing on the steering shaft.

I had a 17.5 briggs and stratton in a JD S100 with the same problem after a different repair. I learned about the vapor recovery system from this vid. I was trying to start the engine with the air filter off. I had the same issue,put the filter in ,no more problem.

Thanks for posting this video. Sure enough my gas line was clogged between the tank and filter.

Is it just me or does anybody else Think it’s crazy there isn’t a screen at the top of the fuel tank to filter out debris. All these problems I’m reading concerning dirt and grime in the fuel line doesn’t surprise me without that screen on the top of the tank. Thank you, Jim for the walk-through. I’m looking forward to giving it a shot in the morning using your technique.

You sir are a god. Painful multiple hours, trying to fix my mower in 100’ heat and damned if you weren’t right gracias