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Jd 200 Clc boom won’t hold machine off the ground

Mallard · 2026-08-11 07:39

I am having trouble with my Deere 200clc, if I lift the tracks off the ground as soon as I release the joystick the machine starts setting itself back on the ground. I disconnected both lift cylinders one at a time and plugged the supply hose and left cylinder unhooked. Then tried to lift the machine, each lift cylinder would lift it partially off the ground but both would instantly set the machine back down when the joystick is released. One of the lift cylinder was recently repacked, neither has any visible hydraulic leaks. What should my next step be? Thanks!

Replies33
  1. #1Simon C2026-08-11 10:03

    Could your boom relief be leaking. I am guessing that you did the cylinder by-pass test correctly. If it was then I would look at the control valve. If your test was not done right then you could be leaking the oil past the packing and machine settling back to ground. I usually would remove both hose on the bottom of the cylinder at the same time to see if one side is leaking while dead ending the cylinder or forcing it to lift the body. Not sure exactly how you tested. Simon C

  2. #2Diesel Dave2026-08-11 10:07

    See circuit releif valve locations in screenshot below. Maybe swap boom down for bucket curl.

  3. #3Simon C2026-08-11 10:08

    Knew Diesel Dave would have the picture showing it for you. Simon C

  4. #4Mallard2026-08-11 10:36

    thanks for the help, i did the test differently, not sure its the right way but it made sense in my mind. I unhooked one of the cylinders hydraulic lines and capped both supply lines to that one cylinder, i left both ends of that cylinder open so it could move freely. i then picked up the machine as much as it would go (front of the track maybe 8" off the ground) then let off the joystick. as soon as i let off the joystick it started to lower to the ground. after testing one cylinder i reversed everything and tested the other cylinder. my thought process was this would isolate each cylinder. as i think through your test it would eliminate the possibility of both cylinders leaking down. i see two ways to do this, which is correct and did i list the steps correctly. (i'm not a mechanic, just someone who doesn't mind working and enjoys solving problems) Test 1: 1. start with the arm vertical. and relieve all pressure on the joystick with engine off. 2.unhook both lines that go to the top of the cylinder. 3. cap the pump side of the lines to keep the oil from going everywhere. and put the hoses from the cylinder into buckets. 4. raise the boom all the way and hold it over relief. 5. while raising the boom oil should come out of hoses but should stop as the cylinder reaches full stroke. if oil continues to come out while the cylinder is held over relief the packing is bad. Test 2: 1. start with the arm vertical. 2. unhook the lines that goes to the bottom of the cylinder that is responsible for raising the boom. 3. cap the pump side of the lines to keep the oil from going everywhere. put the hoes from the cylinder into buckets. 4. lower the boom to raise the tracks off the ground. 5. while lowering the boom oil will come out of the hoses. when i let off the joystick with the tracks say 2' off the ground oil should quit coming out of the cylinder. if oil continues to come out and the tracks lower the packing is bad. if it lowers and no more oil comes out then the problem is somewhere else. am i understanding this correctly? is one better to do than the other?

  5. #5Simon C2026-08-11 18:40

    Your first test would tell you if the packings are okay. Might save some oil by disconnecting the rod end hoses after putting the bucket on something that is high to start the final ascent towards the sky with the boom. That way there is less stroke to go and oil to come out. Once the boom hits the top of its travel and the pressure spikes, if the oil is just pouring out of one or both cylinders, then repair the cylinders. I did one last year for a guy that rebuilt one cylinder, and the other cylinder was leaking outside a hair. Ended up being the rebuilt cylinder was no good. Let us know what you find. Simon C

  6. #6Mallard2026-08-20 11:13

    thanks for the help, hope to get back on this part soon enough. right now i'm still trying to track down the last few leaks i have and have some questions. I have i believe three leaks right now that i need to get fixed. first two are where the main line from the hydraulic pump connects to the valve. one is on the side and the other is on the rear. both use flanged fittings and and they are leaking. I have new o-Rings that i plan to put in tomorrow. When I take the flanges off will the hydraulic tank start to drain or will the fluid not flow through the pump? also i've never installed this type of hydraulic hose connection, is it just line up the hose, and tighten up the 4 bolts in an alternating pattern? The second leak is near the top of the swing motor. I've cleaned it off several times but cant seem to find exactly where it is leaking but it may be where the motor bolts down. on the parts diagram it shows an oring that is probably 8"diameter. is this as simple as just taking the 4 bolts out, lifting the motor off and replacing the o-ring? thanks for the help!

  7. #7Mallard2026-08-20 11:15

    Part #72 is the o-ring I think maybe leaking

  8. #8Simon C2026-08-20 17:09

    Hooking an Eductor or vacuum to the top of the hydraulic tank is a good idea when pulling any hose off the control valve. Blow all around with compressed air before taking apart to get any loose dirt gone. Those control valves do not like dirt. Simon C

  9. #9Diesel Dave2026-08-21 08:45

    When reinstalling the swing motor top head use plenty of grease to help hold the plate # 31 from falling down and off the locating dowel.

  10. #10Mallard2026-08-22 10:11

    Thanks Dave, I got the two supply hose leaks fixed yesterday, it was just the o-rings. I also found a leaking fitting where a small hard metal line connects to the valve block, couldn’t get it to stop leaking by snugging it up so will change it next week. I also want to figure out where all of the oil on the swing motor is coming from. I think it may be that o ring on the top cover, what is the best way to identify the source of the leak? I thought about getting kids side walk chalk and making several marks across the whole swing tower to find where it is coming from? Anyone have a method for identifying the source of hydraulic leaks?

  11. #11Simon C2026-08-22 22:07

    If you wash down a hydraulic leak with brakleen or gas, you can wrap with toilet paper and black tape and will be able to see which section the leak is into the toilet paper. I have done this on antifreeze leaks with success also. Simon C

  12. #12Mallard2026-08-22 23:37

    Thanks, I hot water pressure washed it off before I left, it will be later this week before I get back down to verify where it is leaking. If anyone has any other tips I’d appreciate them. Thanks

  13. #13Welder Dave2026-08-23 00:26

    If you have a JIC fitting leak you can get Flaretite repair sleeves that fit on the male end. I had good luck with one.

  14. #14Simon C2026-08-23 09:08

    I have some copper ones also that work well. Simon C

  15. #15Welder Dave2026-08-23 19:52

    There are a few different ones available. Flaretite are coloured but I'm not sure what material they're made out of. It's a softer metal with little ridges that compress. It was sure a blessing one worked on my track loader boom line.

  16. #16Mallard2026-08-28 18:09

    Got a chance to look at it today and that big o-ring is the only place I can find the oil can be coming from, will change it and one of the other small metal lines next week. Other than the quote below, any other advice about pulling the motor cap off?

  17. #17Mallard2026-09-08 15:52

    Got the o-ring and metal line changed out and I believe I got both leaks fixed. There was a little oil seeping around where the oring was but they may be residual oil coming out from the install. I’ll pressure wash it Friday and find out for sure. Back to the main issue I had. When I lift the machine off the ground it will lower its self down without input from the joystick. Today I pulled both hoses from the rod end of the lift cylinders and capped the lines leaving the metal line coming from the cylinder uncapped and a bucket underneath. I put it at about half throttle and raised the boom to max height and held over relief for 4 20 second periods and no oil came out. I believe this means that the cylinder is good and the problem is somewhere else. What would be the next logical place that it could be leaking by? Thanks for all of help so far.

  18. #18aongheas.macask2026-09-08 16:59

    I f you suspect boom cylinder piston seals are leaking do not disconnect any hoses, raise the boom fully at full rpm and hold over main relief for at least 1minute, ,check the temperature of both cylinders by hand and the leaking cylinder will be considerably hotter than the good one. If both feel the same then you need to check the secondary relief valve pressure for each cylinder, normally you need to adjust the Main relief valve above the secondary pressure to obtain the readings, Without a hyd schematic of your machine I cannot advise further.

  19. #19Simon C2026-09-09 10:34

    Diesel Dave or mg2361 will know what is best to do or check next. Relief valve is my guess. Simon C

  20. #20Mallard2026-09-11 12:45

    Quick update on a few test I did, 1: I raised the tracks off the ground and turn off the pilot lever and turned off the machine, it still lowered to the ground. 2: I switched the pilot controls from backhoe to excavator, no Change. 3. I extended the boom and arm straight out to the position you would check the hydraulic oil level but left the bucket off the ground. I measured it at 11-3/4” off the ground, 10 minutes later it was still in the same position. After I pressure wash it I’m going to lift something heavy off the ground and see if it will hold it up or slowly let it down.

  21. #21Mallard2026-09-11 14:10

    Another quick update, I pressure washed it and then lifted up a skidder which seemed to max out my lift capacity and it will hold it for at least 5 min with no noticeable lowering.

  22. #22Mallard2026-09-13 08:19

    What are my chances that these test point towards a bad relief valve? If so does cleaning them ever fix them or just replacing them? The part number for this relief valve is 4358914 I believe. Thanks for all the help so far.

  23. #23Diesel Dave2026-09-13 09:54

    Referring to the screenshot in post #3, the boom down circuit releif (item #11) is on the bottom of the 4 spool side of the main control valve. You could take it apart to clean , see if there is a piece of debris stuck in it. See screenshot below from the parts catalog. Part # 4372039 .

  24. #24Mallard2026-09-14 08:15

    Thanks for all of your help Dave, when you say “take it apart “ can you elaborate, do you just mean remove it from the block and clean it or actually disassemble it and clean each component?

  25. #25Diesel Dave2026-09-14 10:47

    I mean disassemble the circuit relief valve to clean it. Assuming the relief valve has never been tampered with , take note of the pressure adjustment screw in relation to the lock nut so you can put it back same to the same position.

  26. #26Mallard2026-09-15 11:21

    Thanks Dave, I’ve been digging through the manual to make sure I remove the correct relief valve. Can you double check my work, on the first picture I see item 21: Boom down circuit relief and anti-cavitation valve. Second picture item 78 Third picture, item 78: 4358914 pressure relief valve. Or am I looking at the valve from the wrong side? When I get under the machine the will be the rear most relief valve on the 4 spool side?

  27. #27Mallard2026-09-15 11:51

    Dave, when I looked closer at the Deere website I see I was looking the valve upside down. I believe my first picture is correct but the second two are wrong.

  28. #28Diesel Dave2026-09-15 12:38

    Agreed. The circuit relief valve part # 4372039 in post # 24 is the correct one.

  29. #29Diesel Dave2026-09-15 12:45

    Yes. You can confirm that by following the steel pipe that is directly above the circuit releif valve. The steel pipe should lead to two hydraulic hoses that connect to the rod end of the two boom cylinders.

  30. #30Diesel Dave2026-09-15 13:03

    I maybe full of crap. The boom circuit releif valve is on the 4 spool side but thinking about it I believe the steel pipes for the boom cylinders actually come out from the control valve on the 5 spool side.

  31. #31Mallard2026-09-15 18:49

    Going from memory they come in on the side with the hydraulic tank

  32. #32Mallard2026-09-25 16:09

    Update from today: I changed the boom down pressure relief valve with a new one and there was no change, only place left I can think of is the spool itself. Also I have now changed the o-ring on the top motor cover on the swing motor and it is still leaking. Can I just put some ultra black between the flange halves along with another new o-ring and call it good. That is the only hydraulic leak I can find right now and would like to stop it.

  33. #33Mallard2026-09-29 20:40

    Just wanted to bump this and see if anyone had any advice on my latest two issues? Thanks for all of the help so far, I hope to get this all fixed up before long and really give it a test and see what I have.