John Deere 5020 Engine problems

jake5020

New User
I am having some difficulty with my John Deere 5020. It starts up fine and runs very well under a certain number of RPMS however whenever i get over 1k-2k RPMs after a while. It begins to rev down almost like it is choking down and then it eventually quits. It doesn't get started very often and i am thinking it could be algae in the fuel filter or fuel lines/injectors due to the old diesel. My question is should i clean replace the fuel filter and try to flush out the main fuel lines/injectors or could this be a bigger issue?

P.S. It has Roosa Master 687 fuel pump i believe so do i not have to prime/bleed the fuel system because have seen post of it being an auto bleeding system.

Really hope i get a response from someone, i am a college kid who inherited the 5020 from my grandfather and im trying to figure out everything i can about it to keep his legacy alive so someday i hope to restore. it.
 
Sounds like injection pump needs repair, confirm it by trying this. With engine running and starting to slow down loosen the two screw timing cover on the injection pump
side. If engine runs OK WITH the fuel leak but dies with cover tight, it's confirmed it needs repair. DON'T run it much longer or you risk shearing off the retainer pins,
locking the hydraulic head and breaking the drive shaft. I repair a lot of pumps, but when they come in with a broken drive shaft it gets expensive FAST...
 
(quoted from post at 19:34:56 03/15/23) Sounds like injection pump needs repair, confirm it by trying this. With engine running and starting to slow down loosen the two screw timing cover on the injection pump
side. If engine runs OK WITH the fuel leak but dies with cover tight, it's confirmed it needs repair. DON'T run it much longer or you risk shearing off the retainer pins,
locking the hydraulic head and breaking the drive shaft. I repair a lot of pumps, but when they come in with a broken drive shaft it gets expensive FAST...

Ok thankyou I will definetly try this. If this does not work are there any more alternatives. Could it be trash in a file line or injector. Like I said the fuel has been there for a few years now and I m wondering if some algae has developed that has started to prevent fuel flow through the filters or lines.
 
(quoted from post at 19:49:45 03/15/23)
(quoted from post at 19:34:56 03/15/23) Sounds like injection pump needs repair, confirm it by trying this. With engine running and starting to slow down loosen the two screw timing cover on the injection pump
side. If engine runs OK WITH the fuel leak but dies with cover tight, it's confirmed it needs repair. DON'T run it much longer or you risk shearing off the retainer pins,
locking the hydraulic head and breaking the drive shaft. I repair a lot of pumps, but when they come in with a broken drive shaft it gets expensive FAST...

Ok thankyou I will definetly try this. If this does not work are there any more alternatives. Could it be trash in a file line or injector. Like I said the fuel has been there for a few years now and I m wondering if some algae has developed that has started to prevent fuel flow through the filters or lines.

Also could bad fuel have caused the injector pump to go bad or clog up? If so is it possible to get a very high powered fuel treatment as well as putting new diesel in the tank to resolve the issue.
 
(quoted from post at 20:09:00 03/15/23)
(quoted from post at 19:49:45 03/15/23)
(quoted from post at 19:34:56 03/15/23) Sounds like injection pump needs repair, confirm it by trying this. With engine running and starting to slow down loosen the two screw timing cover on the injection pump
side. If engine runs OK WITH the fuel leak but dies with cover tight, it's confirmed it needs repair. DON'T run it much longer or you risk shearing off the retainer pins,
locking the hydraulic head and breaking the drive shaft. I repair a lot of pumps, but when they come in with a broken drive shaft it gets expensive FAST...

Ok thankyou I will definetly try this. If this does not work are there any more alternatives. Could it be trash in a file line or injector. Like I said the fuel has been there for a few years now and I m wondering if some algae has developed that has started to prevent fuel flow through the filters or lines.

Also could bad fuel have caused the injector pump to go bad or clog up? If so is it possible to get a very high powered fuel treatment as well as putting new diesel in the tank to resolve the issue.



This is a video of what happens whenever I idle to high and it chokes down. I tried to idle it back up at the end but it still died.
 
Id be very surprised if it was an injector because it wouldnt
run fine for awhile then die. Ive never worked on a 5020 but
the smaller ones have a charge pump on the side of the
block. Could dirt or Algae be stuck in the feeder line or tank?
Does it get better if compressed air blown out line? If
everything checks out there then you are kinda down to
whats already been suggested main fuel pump. Oh and make
sure those two round stacked fuel filters are all on tight and
bleeders shut that would be the other thing I forget on the
4020
 
(quoted from post at 20:33:18 03/15/23) Id be very surprised if it was an injector because it wouldnt
run fine for awhile then die. Ive never worked on a 5020 but
the smaller ones have a charge pump on the side of the
block. Could dirt or Algae be stuck in the feeder line or tank?
Does it get better if compressed air blown out line? If
everything checks out there then you are kinda down to
whats already been suggested main fuel pump. Oh and make
sure those two round stacked fuel filters are all on tight and
bleeders shut that would be the other thing I forget on the
4020

Yes it is very possible the diesel in the tank has been in there for almost 7 years. I have tried treating it multiple times but I have heard that it could be algae built up in the main line or the tank. Should I just take the main feeder line from the pump to the filters off and flush it out. I have not tried blowing compressed air out of line. I don t necessary know how to do that this is my first time really working on a diesel John Deere besides driving and working with them.
 
. The addition of additives will not clean up dirty fuel or clean lines and filters .
The entire primary system requires draining , flushing and filters . This includes the sump n the fuel tank .
As previously stated . If opening the pump cover solves the issue . Repair it now instead of later .
 
Fuel filters change first if its even a question I suppose. Then
fresh fuel after draining out the old fuel and looking in the tank
for junk and dirt. If thats all good go ahead and fill it up a
good ways like 3/4 full to make it easier to prime. Then pull
line off charge pump inlet and watch it go into bucket. Does it
flow good for a bit then stop and slow down? Or does it
continue indefinitely. If it continues for longer than it takes to
die normally no plugging issue in tank or first line. This would
mean your problem is farther down and would require
replacing a component. If thats done and back together its
time to prime. Use bleeder on filter till you have fuel at the top.
The little hand lever on the charge pump is primer. Then time
to see if the filters and fuel fixed it. If your lucky it will. How far
north are you is the other simple question and did he have
winter fuel in in. Its been cold in the mornings and thats kinda
what they do if the tank is gelled and its warm enough to thaw
the lines and filter.
 
Just something simple to check. Make sure
the air breather is fairly clean and not
packed full like a rat nest. A filthy air
filter can cause similar problems.
 
I rather bet you are correct. Return plugged full of ground up flex ring. Good call!
 
(quoted from post at 03:51:50 03/16/23) Fuel filters change first if its even a question I suppose. Then
fresh fuel after draining out the old fuel and looking in the tank
for junk and dirt. If thats all good go ahead and fill it up a
good ways like 3/4 full to make it easier to prime. Then pull
line off charge pump inlet and watch it go into bucket. Does it
flow good for a bit then stop and slow down? Or does it
continue indefinitely. If it continues for longer than it takes to
die normally no plugging issue in tank or first line. This would
mean your problem is farther down and would require
replacing a component. If thats done and back together its
time to prime. Use bleeder on filter till you have fuel at the top.
The little hand lever on the charge pump is primer. Then time
to see if the filters and fuel fixed it. If your lucky it will. How far
north are you is the other simple question and did he have
winter fuel in in. Its been cold in the mornings and thats kinda
what they do if the tank is gelled and its warm enough to thaw
the lines and filter.

I am located in Tennessee. The diesel has been in the tank for about 8 years now. I really do think that s it s the issue I have had a lot of guys tell me that the algae from the moisture build up will block your filters which makes sense as to why it chocked down when at a high RPM. I also have had another small issue I d like to run by you. With the same tractor sometimes the ignition switch acts up. I turn the key and it doesn t turn over. I believe it s a wire from the starter to the switch that has gone bad becuase if you move those wires around connected to the switch and get it into the right spot it will turn over. I have pictures and videos as well so that y all can hear what it sounds like.
 
First make sure fuel is good. I have started tractors that sat for 15 years never started that the old fuel was fine. Filters need changed anyway. With line disconnected before actual fuel pump check flow. You can manually check pump by hand then you will get to the most likely problem the injection pump take it to a good shop and $1000+ later you will more than likely have found your problem.Starter wouldnt hurt to have it checked but 90% of starting problems are connections or a celenoid that has a mind of its own. Nice to preserve the 5020 and sometimes its easier and cheaper and less frustrating to rely on an experienced mechanic for me anyway. One thing I do know that paying $150 an hour at JD adds up quickly on a $10K tractor
 
A quick and easy way to troubleshoot the tank is to disconnect the line from the tank and hook up to a temporary one. If the problem persists after doing that, you can eliminate the tank as an issue.
 
(quoted from post at 21:53:08 03/17/23)
Have you did Dieseltech's suggestion yet? What was the out come.
DO THIS!! Although after setting that long it could very well need a new filter. If loosening the timing window on the injection pump makes it come back up to RPM you could have the best 500 gallon fuel supply feeding your filters with a 1 inch line and the tractor would act no different. I know that is an exaggeration but the fact is any time you spend trying to correct a problem that does not exist is wasted time. The timing window is about a 5/8 x 1 1/2 inch rectangle with two screws. What happens is a plastic ring that is somewhat flexible inside the pump is deteriorated by the fuel, heat and age. It starts breaking apart and pieces float around in the housing. The small line coming off the pump is the return, the fittings that screws in the pump for it has a check valve in it. That valve plugs with the pieces and the pressure in the housing gets too high. The high pressure causes the fuel delivery plungers to not be able to function correctly to pump the fuel to the injectors so the problem you described happens. Relieving that pressure allows everything to correct and the engine picks up RPMs. Dieseltech is in the pump repair business on Indiana, many posters here send there pumps to him for repair. I have only heard good things about his work and how reasonable his prices are, his email is open.
FYI, due to file size restrictions you will only be able to post a very short video here, like under 10 seconds. Otherwise if you can upload it to YouTube then you can post a link to it here.
 

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