JD 4010 fuel or timing issue?

I just bought a 4010 gas tractor on friday. When I start it it turns over, starts, runs, for a second then dies. It does this 5 or 6 times before it will stay running. Then it is so loaded up with fuel it puffs out a little black smoke and smells like gas. Then the tractor runs and drives fine. But when I shut it off it will stay running for a few seconds witch makes me think its a timing issue. The guy I bought it from had a new carb put on it so Im thinking it just needs adjusted. He said its the "new" style carb. I have know idea what the "old" style is or if this is a "new" stlye. Anyway I have know clue how to adjust it so Im asking for some advice. I have the operators manual but its no help on adjusting. I can take a picture of the carb tomorrow night if that would help. Thanks alot

If you turn the engine off it should stop as there would be no spark so something is wrong somewhere and it isnt the carb because without spark an internal combustion engine doesent run without spark on gasolene. Maybe thats why it sold cheap wouldnt be the first tractor sold below price cause people knew something was wrong.

I dont feel anything is "wrong" with it I just think it needs adjusting. Im just not sure what to adjust! LOL

i have no experience with that particular model, just brainstorming here... is that the infamous 24V electrical system? is the charging circuit somehow backfeeding the ignition circuit?

It should be a Marvel Schebler with the load screw on the side facing out and is located at the lower rear. The idle screw is angled in from the top rear. These carburetors have an accelerator pump diaphram in them and if it starts to leak it can cause a rich mixture. I would call your friendly dealer or a good local mechanic and make sure the "new style" carburetor they put on it will even work with that tractor before you try to adjust it. You may not be able to adjust enough if it"s not the right cfm.

Nope, not the case. Gas tractors will run without spark, it is called dieseling. Often times this is caused by carbon buildup in the combustion chamber from running too rich, the hot chunks of carbon pre-ignite the gas. I would give it a general tune-up, start with the carb. Just above the fuel line on both the zenith and the marvel-schebler (yours has the zenith from looking at your pics) carbs is the idle mixture screw, set the throttle at idle, and then adjust the idle screw for highest RPM. Then set the load circuit, should be a t-handle adjusting screw at the bottom rear of the carb, below the fuel line. Start at 1 3/4 turns out for your zenith,adjust at PTO speed for smoothest running. Also, your carb heater block is set to its cold weather setting, it is the block on the manifold above the carb, it could cause the dieseling issue, unbolt it and you will see how it will reattach and not direct hot air around the carb. For timing it, hook a timing light to #1 cyl, open the timing window over the flywheel just in front of the brake pedals, run the tractor to 1900RPM, loosen the distributor clamps and line the "20" degree mark up with the mark on the bellhousing. All this came out of my 4010 operators manual, hope it helps.

T.E.C, 4010s came with either a zenith, or a MS carb, and Justins has a zenith, it just sounds like it needs a tuneup.

It might be pre-ignition./ carbon buildup in the combustion chamber.
Nice price on the tractor, minor bugs to work out.
Good Luck
k

justin, i see by your picture that the head has been worked on. was this tractor used for tractor pulling? i would take a compression test and see if it is higher than it should be, that would cause it to run after you turn it off, or you could put some premium gas in it and see if it turns off normally. just my 2 cents, chuck

Is this a cold or warm start? Sounds like
she's all loaded up, this tractor was built
to pull a plow not putter around. If your
oil pressure is good and if it is not
running hot put 93 octane gas in it and a
quart of marvel mystery oil and field
work it (plow or disk for 1/2 day) and
then see what you have. Does it have
fresh fuel in it? The old gassers were
notorious for being cold natured and
running rich when cold.

Replace the ignition switch. Have had this happen on mine a couple of times. It will run off the start circuit but will not keep running.

Start out by adjusting the carburetor first. A real rich fuel mixture will make it do exactly what you are talking about. I would still check the spark plugs to see if they are fouled but adjust the carburetor first either way. If it is too rich it can foul new plugs fast.

I do them a little different than some on here have told you. I always adjust the load or high side first and then adjust the idle mixture an speed. I have found that this works the best. A too rich load will effect the idle more than a too rich idle will affect the load.

1) Get the tractor up to operating temperature.

2) The load adjustment is on the back of your carburetor. With the tractor running wide open slowly turn the adjusting screw in. Go in until the tractor starts to stumble/miss. Slowly open it back up until it runs smooth. Then depending on what you are doing or the temperature you need to open it a little more. In warm weather and light load I only go 1/2 turn after running smooth. Under heavy loads maybe 3/4 to 1 full turn. In cold weather you may have to go 1 turn out after smooth running even under light loads.

3) Now bring the tractor down to idle. Then adjust the idle mixture to get it to run smooth. This screw is at a 45 degree angle on the back top side of the carburetor. Takes a flat screw driver. Run the speed up and down a few time to see how it takes throttle. If it tries to die open the idle mixture screw 1/4 turn at a time.

4) If the idle speed is too high or low adjust it with the stop screw on the butterfly cross shaft.

You may have to repeat steps 2 & 3 several times to get it to run just right. You will have to play with the load adjustment as the weather changes and your load demands change. I usually ran them a little lean under light loads just to keep from fouling the spark plugs as much. Don't do this under heavy loads as it will make them run hot.

Now after you have adjusted the fuel mixture you check the ignition system out if you are still having problems. I would clean the points first making sure the rotor button and cap contacts where clean. Then go to timing if those don't get the job done.

Now my opinion on JD gas tractors. I don't own one with more than two cylinders any more. The six cylinders are not as bad but the 3 & 4 cylinder are horrible to keep running right. The 1020,2020,3020, 3010 and etc. are the worst things to keep going with this new gas. They either foul the plugs or will not take throttle. They also are hard to start hot. We never had these issues as bad until about ten years ago. Even with higher octane fuels they still are a head ache.

I worked a week on a JD 3020 gas. I never did get it to run correctly. I even changed the carburetor to one that ran well on another tractor. I replaced the complete ignition system with a known working one. I replace the intake gaskets. Checked the compression. I never did get it to start when hot unless you would wait 15-20 minutes. Then it would fire right off. You could run the battery flat when it was hot and it would not start. When it got cold outside you could not make it run right. Either black smoked or would miss and stumble. I eat the repair bill as I did not make it any better. The guy took it to several other guys and none of them could get it to run right either. He finally changed the engine to a diesel one. Sold the other one to a salvage yard. I hope they did not sell it as a complete motor.

I had a JD 4010 gas I used on my feeder wagon. I got to have to change the plugs once a month to keep it where it would start and run. I finally sold it and bought a diesel. I will gladly keep a diesel plugged in the winter as having to mess with a gas year round!!!

The other gas tractors don't seem as bad. The IH run fine. The little Fords do well but the JD bigger ones are a nightmare.

The 24 volts where DIESEL only. They really where not that hard to keep working. I have a JD 4010 that still is the 24 volt and it will out start the one I have that is 12 volt. The 12 volt one had been overhaul too.

I am willing to bet that who ever sold him the tractor has it set way too rich. Then the fuel that is not burnt is letting it diesel a little after he shuts it off.

he had said someone put the new style carburetor on
it. This would be one from a 4020 or 66 or 7700
combine gas engine which is a Marvel Schebler. A lot
of guys got rid of the Zenith for more accurate
tuning.

Welcome to the world of john deere gas tractors. JUNK JUNK JUNK!!! Good luck getting and keeping it running correctly. Save yourself some trouble and sell it to another sucker and put that money toward a diesel.

Fuel inject it ....

2 things to add

if you are a young guy like me and grew up on fuel
injected / electronic ignition engines - check the
ignition stuff first (points, condenser, coil,
wires, cap, rotor) They are easy and need to be in
good working order to get the fuel right.

then everything JDSeller said with an emphasis on
the adjusting the carb with the seasons and load.
I have a JD Gasser and it needs adjustment about
every three months as the weather changes.

-paul

Thanks for the info guys! I really appreciate it. I will try and get to it this week. My son has football practice every night and by the time homework and supper is done its 9pm. LOL But when I get it done I will post results. Thanks again