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

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.

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.

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.

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 .

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?

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.

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?

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.

Mallard said: 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. Click to expand... Agreed. The circuit relief valve part # 4372039 in post # 24 is the correct one.

Mallard said: When I get under the machine the will be the rear most relief valve on the 4 spool side? Click to expand... 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.

Diesel Dave said: 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. Click to expand... 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.

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

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.

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.