Tractor Under Load

   / Tractor Under Load #1  

bikerzing

Member
Joined
Oct 5, 2016
Messages
31
Location
Tomah, WI
Tractor
1970 John Deere 1020
I just noticed today as I was moving residual snow filled with gravel back onto the driveway that the tractor seems to run "strange" under load. It almost sounds like the choke is open, but I made sure it was pushed all the way in. As you can tell, I am not much of grease monkey, but willing to jump in when I have to. So I have a 3-cylinder gas John Deere 1020. It has no problem idling at 500rpm or at 2500rpm. But as soon as I start doing bucket or back blade work it sputters.

This just got me thinking about the hydraulic fluid. I have two small leaks, one under the tractor at the hydraulic connections and a second at the bucket cylinder. Could that be caused by low hydraulic fluid? I never did check that and the tractor has been sitting idle for about a month.
 
   / Tractor Under Load #2  
Is the fuel system clean with no water and good filters? Can carberator jets be adjusted?
 
   / Tractor Under Load #3  
Forget about the hydraulic leaks causing the problem unless they are some how getting into the carb intake.

It doesn't take much fuel flow for low or high idle but it does as you increase the load. Make sure you have adequate fuel delivery from the tank outlet to the carb fuel bowl. There is a tank strainer or maybe a sediment bowl so check them for clogging (crud, ice if the temperature below freezing). Make sure the fuel line is not kinked and if there is a screen in the carb inlet elbow, check that. If that checks out you may want to consider checking the carb fuel bowl for water, ice and/or crud. Finally, the main jet maybe clogged.
 
   / Tractor Under Load #4  
Sounds like it's starving for fuel, it shouldn't have anything to do with your hydraulics. Clean the carb and put some fresh gas in it.
 
   / Tractor Under Load #5  
Before I tore the carb off for a new condition.. I'd add some seafoam and ride it around a bit. A small bit of water can cause the lean running condition and sea foam can move it out of there. I would also find the main jet, and open it a quarter turn.


It's a $7.00 try vs. a kit and lots of time.
 
   / Tractor Under Load #6  
Fuel trouble is likely, especially this time of year, but it might be air. When it sputters, what color is the exhaust? When under load, it needs more fuel AND more air. If the air cleaner is plugged, it is effectively choked when you want more air than it can supply, and would likely make the exhaust dark. Check the air cleaner, too. Creatures seem to like them for making nests and storing food.

If the air supply is clear, maybe check the governor (if it has one) while checking the other fuel stuff. If that linkage is sticky it may not be able to add enough fuel when the engine slows.

- John
 
   / Tractor Under Load #7  
When I first got my '66 1020, it did the same thing. On the carb fuel inlet there's a screen that can get clogged, and mine was. I also drained the tank and blew out the lines on either side of the lift pump. A local NAPA store had a rebuild kit for the carb, so I did that as well. Probably the biggest culprit was the dirty inlet filter, but the carb didn't suffer from the rebuild. It's worked great since.

I do have some worn NLA parts on the governor that cause slow throttle response. It picks the load up fine, no sputtering, just a little sloow on the pick-up.

HTH Mark
 
   / Tractor Under Load
  • Thread Starter
#8  
Going to try seafoam first. My fuel pump doesn't have a screen. After doing a little digging, it looks like they must have changed versions of fuel pumps on these and got rid of the fuel pump that uses a bowl and screen. If the seafoam doesn't work, I will disassemble the carb. Lord knows when the last time that thing has been disassembled. I will have to look for a rebuild kit.
 
   / Tractor Under Load #9  
All good info posted. My tractor manual recommends changing the fuel filter when you notice a loss of power......it's not hours based.
 
   / Tractor Under Load
  • Thread Starter
#10  
I dug into my service manual and found there is a strainer assembly at the inlet elbow of the carb. There is no fuel filter.
 
 
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