I recently purchased a John Deere LA105. It has about 4 hours on the engine, and was been stored in a climate controlled environment for around 9 years prior to my purchase. Unfortunately it spent most of those 9 years with gas in the fuel system. I have purchased a carb kit from John Deere and rebuilt the carb. I have also replaced the fuel shut-off solenoid. The mower is still not running correctly. I have a video of it running on Youtube. I have attached the link as a text document since I cannot post links yet. It runs mostly fine at low throttle, but cuts out when at high throttle, and gets worse when the engine is under load. Can anyone help, or possibly point me in the right direction?
John Deere with Briggs & Stratt not running correctly
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BlazNT
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The first thing to do is clean out the gas tank. Remove it from the mower and rinse it out. Not a speck of dirt. Next is to replace everything from the fuel tank to carb except for the fuel pump. Remove the carb and clean it really really really well. Compressed air from the carb throat to the fuel pickup side. Never from the pickup side to the throat. I take old speaker wire strands and run them through every hole I can find in the carb throat back to the fuel pickup side. Then spray with carb cleaner making sure not to get any on anything that is not metal. Gasket and rubber do not like carb cleaner. Fresh clean fuel then try again. On a machine that has had fuel in it for that long, you must do all of this. Fuel lines must be replaced with new ethanol resistant fuel lines and the carb must be cleaned to a spotlessness on the inside where you can not see. All the little passages must be clean. Even after all of the cleaning you may still have to replace the carb. If you do replace the carb make sure you still do all the other things of the new carb will get the same problems as the old carb. You must clean the fuel system to like new status or it will all come back in short order.
Thanks for taking the time to help me. I have drained the tank, but can't easily clean it since it's mounted below the seat and rear fender. It looks like it would be difficult to remove. I have cleaned and checked all of the fuel lines, and they're all clear, and I'm getting good fuel to the carb. I cleaned the carb when I installed the repair kit. I DID NOT run any wire through all of the carb passages though. I will disassemble it again today and do that.
BlazNT
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I thought I got my point across about the fuel lines but I guess not. What happens is the fuel lines start flaking rubber into your fuel. It then gets into your carb that can not handle the particles. This now causes what problems you have. You would think that lawn mower and engine manufacturers would know not to use the fuel line they do but money in the pocket always prevails. You do not have to replace the lines either but I can guarantee you the problem will come back if you do not change them.
Boobala
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Sorry for the long delay. It's been a busy weekend. I have now replaced all fuel lines, replaced the in-line fuel filter, checked, cleaned, and re-gapped the spark plug, and disassembled the carb once again to run wire through all passages. None of this has made any noticeable difference. I took some photos of the disassembled carb; can you see anything that might be causing the issue? (link is in attached txt document again.) I'm starting to consider just replacing the entire carb. View attachment link.txt
Thank you for your valuable input.
Boobala
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Look fella I posted that sarcasm BECAUSE the tech offered YOU advice that was IMPORTANT to US .. as well as you,.. we are NOT there seeing, touching, smelling or hearing what's going on, maybe you don't understand.. it's BULLSCHITT to O/H a carb and then have a bunch of schitt go into it, because the fuel system was NOT PROPERLY cleaned. these carbs are sensitive to dirt, ( foreign matter) and you CAN'T get the carb to function correctly if the rest of the system is not really clean, and possibly introducing dirt into a clean carb, He told you because it's IMPORTANT ! you save re-diagnosing the same problem over again ! ALSO , it would help if you posted your machines info, JD LA105 is the SERIES we need the model and engine numbers see example ...
bertsmobile1
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At the bottom of the white tube is a small chunk of brass.
That is the main jet, push it out slowly noting which way is up
The rebuild kits usually come with a new one cause you take the white plastic housing off tip or blow on it and the main jet ends up in that parallel universe with all of the lost keys and missing left socks.
It is held in place by that tiny O ring
It has a tiny hole in it.
Without it there the engine will start & idle fine but when the throttle opens wide the engine will flood, cough splutter & do what we call 8 stroking.
That is the main jet, push it out slowly noting which way is up
The rebuild kits usually come with a new one cause you take the white plastic housing off tip or blow on it and the main jet ends up in that parallel universe with all of the lost keys and missing left socks.
It is held in place by that tiny O ring
It has a tiny hole in it.
Without it there the engine will start & idle fine but when the throttle opens wide the engine will flood, cough splutter & do what we call 8 stroking.
Boudreaux In Eunice La.
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I saw the video and I think the idle cuircut is clogged also.... I do a lot of those carbs and a 3rd of them need the welch plug taken out prior to a carb dip........
Bert is correct on that brass jet..... Clean the hole well.... Also there are smaller holes in the long tube that goes in the white tube...
A bunch of them and they need cleaning also with a fine wire..........
Let us know Mon Ami ~!~!
Bert is correct on that brass jet..... Clean the hole well.... Also there are smaller holes in the long tube that goes in the white tube...
A bunch of them and they need cleaning also with a fine wire..........
Let us know Mon Ami ~!~!