Introduction: Early John Deere 3020 Powershift Front End Loader Hydraulic Re-plumbing

About: I am by nature a geek and am not ashamed to say so. I decided to create this instructable account because I figured in my learning process I could also teach others. Feel free to look at my existing instructab…

I bought my first tractor recently an early model 1968 John Deere 3020 tractor with the power shift transmission. The tractor came with a front end loader that had its hydraulic lines plugged into the rear ports. The bonus is that it has a front end loader the bad side is that if I want to run any attachment that has hydraulics I cant, without unplugging the loader at least. Since this is an early model JD 3020 there is no power beyond block which would be a pretty simple way to get the front end loader off of the rear hydraulics. So I reached out into a few internet forums and found some really helpful people to help me with this project. If it wasn't for the people at and I would not be able to write this instructable. A special thanks to "Tx Jim" for getting me started and answering questions. There is not a lot of documentation on doing this specifically on the PowerShift Transmission so I thought I would put the whole project here.

This instructable will be a step by step with images, video, part numbers and approximate cost of completing. I was going to do this at the same time as a hydraulic fluid and filter change but we will do that in another instructable.

Please understand I am by no means an expert on tractors and again if it wasn't for the kind folks on the previously mentioned forums I wouldn't be doing this at all.

Also please note while I wanted to be able to video this entire process I skipped around a little bit due to the amount of hydraulic fluid on me and everything else I didn't want to damage my camera.

Step 1: Lets Get the Parts, Supply Side

Now to do this project you are going to need some parts, specifically some "T" fittings, the part numbers that I purchased are mostly from John Deere or Tractor supply for small adapters etc.

For the supply line side of the loader we need to get a "T" that will fit on the right side just behind the brake pedal. There are two options for this "T" fitting. JD part number AN140263 ($25) or AN140264($50). There is a difference in these two parts and not just in price. The part where it goes into the console of the tractor (not the lines) is a different size. Again where it connects to the tractor the OD(outside diameter) is .5" on the AN140263 and .625" on the AN140264. If you tractor already has the reducer on the console then you can use the AN14023, otherwise you need the AN140264. My suggestion is to buy both and return the one you do not use.

You also have the option of using the rubber hydraulic line OR you can use hard line but you will need a tubing bender etc. For this tutorial we are going to use the rubber line. Depending upon the size of your current hydraulic hoses running from the loader you may need to either buy new hoses OR adapters to make them fit. Make sure you have all of the fittings or adapters needed to go from your hose to the part number listed above.

Step 2: Now for the Parts on the Return Side

The return side on the PowerShift Tractor is a little tighter than the Syncro range but luckily it looks like they use the same parts. So while I am working on the Powershift, the same applies to a Syncro Range Tractor. You need another "T" fitting JD part number AK40462 ($36) and a 90 degree fitting JD part number AK40464($25)(or part sub JD AT28379).

Again you could use hard line to go from here and the fittings might change a little bit, it would need to be a long line and will require a lot of bending. Either way make sure you have the correct adapters to go to your return line on the loader. I wish I could tell you what adapters you need but it all depends on the hoses you have.

Of course you also need John Deere 303 rated hydraulic fluid which you can buy from John Deere at $60 per 5 gallons or at Tractor Supply for around $30.

Step 3: Closed Center Control Valve

Depending on your loader control valve there is another important change that needs to be made. The tractor is a closed center system, so if your valve is set up for open center you either need a new valve or you need to change the conversion plug on your valve to a closed center plug. If you do not either replace the plug or the valve depending upon its capabilities, this conversion will not work. In my case I was able to locate a closed center plug and switch my existing valve over.

Changing the conversion plug to the closed center plug was really easy, using a HUGE socket pull the old one out then put a little bit of hydraulic fluid on the new plug to hold the o-ring in place and thread new plug in.

Step 4: Change of Heart

When I originally set out to do this I was going to do a complete hydraulic oil and filter change, then it dawned on me that if I do that and for some reason this doesn't work and I need to revert back I would be losing twice as much fluid. At between $30 to $60 per 5 gallons that could get quite expensive. So I decided to just keep the fluid in it and lose as little amount of fluid as I could in this process.

Step 5: Now for the Return Line.

As I previously mentioned the return line side is a little more tricky to get to and has an extra fitting involved. Mine is a little more tricky because of the front end loader support goes all the way to the rear. Yours will most likely not be that way though. In my case I ended up buying new hose to run the return line as well.

  1. The first step to changing the return line is that we need to disconnect BOTH batteries.
  2. Once you disconnect both batteries, remove the left side battery.
  3. Then remove the battery box. This will give you a little more clearance to get to the line we need to make changes to.
  4. Set a bucket under the tractor to catch the fluid that is going to come out. I lost between a 1 and 2 gallons. (Depending on if your bucket is clean you could reuse this fluid. My bucket was not clean)
  5. You will also need to remove the rear filter cover and filter to get better access to the line. Be careful not to damage the filter port or get any crud in it.
  6. See the images and video for location of the correct line as there are three lines here. Remove the large hydraulic line from the 90 degree fitting.
  7. Then remove the 90 degree fitting.
  8. Again using thread tape or pipe dope put some on the part that goes into the tractor on the new "T".
  9. Thread the new fitting into the tractor ensuring that the fitting is aligned with the old line and is tight enough to seal.
  10. Take the new 90 degree fitting and thread it onto the end of the new "T".
  11. Now remove the return line from the front end loader and find the best route to run the hose. You don't want the line rubbing and moving on too many things as it can cause premature failure of the line.
  12. After you find the best route, connect to hose using adapters to the new 90 degree fitting.
  13. Use zip ties to hold your hose away from moving parts or the ground. Make sure they are snug but not overly tight.

The return line is now installed, lets install the easy one...

Step 6: Changing the Supply Line Side.

Now we are going to change the supply line side.

Right behind the brake pedal on the right side is a 90 degree fitting and a hydraulic line.While doing this try to have a bucket under the tractor to catch the fluid before it hits the ground. It will run down the side of the tractor so it is hard to predict where it will fall.

  1. First remove the hydraulic line.
  2. Then remove the The 90 degree fitting.
  3. Find out which of the two "T" fittings fit your tractor. I my case it was the smaller of the two, AN140263. Put either thread tape rated for petroleum oils OR pipe dope on the threads going into the tractor console. With pipe dope you need to get a good layer but remember that more is not good with the paste. With the thread tape, make sure to wrap it opposite of the threads so it doesn't ball up when you thread it into place. Thread the new fitting into place ensuring that it matches the position of the hydraulic line, but is still tight.
  4. Re-connect the hydraulic line to the "T".
  5. Then using your adapters or new line take the supply hose off of the rear port and connect it to the other side of the "T". Make sure to tie your hydraulic line out of the way of your brake pedal. You can use zip ties but you don't want to make the zip ties too tight or you can damage your line.

That is it, your supply line side is done.

Step 7: Adjustments to the Loader Control Valve


While I did not video it, I do want to reiterate that you need to make sure your control valve is set up for closed center hydraulics or this will not work. Most control valves have the capability of being switched to closed center with the use of a closed center plug. So how do you know if your valve is open or closed center? It is actually pretty easy to tell. Remove the hose on the supply and return side. Using a blower nose on an air compressor line, blow into the supply side and see if air escapes through the return side. If air does pass through the valve then it is open center, while if no air passes through it is closed center.


Depending on the features of your front end loader control valve you may have a pressure relief valve on the control. The purpose of the pressure relief valve on an open center system is to protect your hydraulic valve from over pressure. In a closed center system your pump should cut off at a certain pressure.

If you do have a pressure relief on the valve then this needs to be adjusted. Most manufacturers set their relief at the factory between 2000psi and 2500psi. We need to tighten it all the way down as a pressure relief is not needed for closed center systems. Check the manufacture information on which way turns up/down the relief setting.

Since a lot of these are set up similarly I will list out my steps.

  1. Remove the acorn nut (cap) from the pressure relief valve.
  2. Loosen the jamb nut
  3. Tighten (righty tighty) in my case, the center of the relief valve ALL the way in. This sets the relief PSI at the maximum setting for the valve or disables the relief completely. Trust me its not the other way but check to be sure.
  4. Tighten the jamb nut
  5. Reinstall the cap and tighten.

Warning failure to do this step or turning the pressure relief valve the wrong way will allow fluid to leak across the relief causing a horrible screaming sound. Which will in turn make you think you broke something or that you need a new control valve costing about $300. Fortunately I found my mistake and was able to adjust the relief before I purchased a whole new valve. But this was a big failure on my part to do this at first and almost cost me a bunch of money. Watch the video to hear the horrible sound that the tractor makes when fluid leaks by.

Step 8: Refill Hydraulic Fluid.

We know we lost some fluid so we need to refill the tractor to prevent damage. Go ahead and add about as much as you lost. Note that when you check the stick it will appear over full, that is ok.

Now go ahead and install your batteries and reconnect.

With the throttle set about 1/4 bump the tractor starter a few times and check your fluid again. The turning of the engine should have pulled that extra fluid back into the filter. Add more fluid to keep it into the safe zone.

Now go ahead and start the tractor let it run for about 10 - 15 seconds and cut it off. Check the fluids again and add if needed.

Go ahead and start the tractor up and set throttle about 1500 RPM. Now using the loader control, move the loader and bucket to their full extent both ways several times. This will get the air out of the valve and the hydraulic lines. Cut off the engine and check the fluid again, adding if needed.

Repeat this process another time or two until you are sure that the fluid is where it needs to be.

Step 9: Leak Check

Now if your tractor is not already running go ahead and start it up. Set your throttle to about 1500 RPMs. Make sure the tractor is in park and the wheels are chocked. Jump off of the tractor and check all of your new connections for leaks. If you find a leak shut off the engine, tighten as necessary and repeat. You don't want to be messing with the hydraulics under pressure so make sure to turn off the tractor.

Provided the tractor is good and warmed up, jump back on the tractor and start it. Crank the RPM up to about 2200 RPM (PTO speed) check for leaks again. Shutting off tractor if a leak is found adjust as necessary. If no leaks are found, move the loader and bucket to their full extent several times to get any remaining air out of the lines.

Step 10: Thank You

Now we have a front end loader that is not dependent on our rear hydraulic ports so that we can use other equipment at any time and still have our loader functionality. Between all of the components, hoses, and fluids this probably cost me somewhere around $300, subtract the $70 in fittings that we didn't use and we are closer to $230-$250.

Again a special thanks goes out to the guys at Yesterdays Tractor Forums specifically "Tx Jim", "Hay maker2" and a few others, for their assistance and guidance in changing this over. I couldn't have done it with out that community and sincerely appreciate the knowledge they are willing to share.

I posted this instructable and videos to help others who end up with the same type of tractor with the same issue and need some kind of documentation to assist. To my understanding these instructions would also be very similar if not the same on a John Deere 4020 FEL.