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Case 1840 arms won’t lower…

swanson50 · 2022-07-10 17:09

Hey all, Long time lurker, first time poster. I bought a case 1840 project machine. I’m in the final stretches here and putting things all together. I tied off the auxiliary system to be able to use the rest of the machine until I give the aux system some attention. However, after I hooked all the lines back together, the lift arms raise fine but will not lower. The bucket cylinders work just fine both directions. Additionally, I can lower the arms if I turn off the machine and depower the hydraulics. Any recommendations would be so helpful. Thanks! Pics if anyone is interested in the ol girl.

Replies16
  1. #1jacobd2022-07-10 21:14

    What do you mean you "tied off the auxiliary system?" Iirc if you simply capped off the power beyond port in the loader control valve the system will act as though there is too high a load on the auxiliary circuit and it will bypass through the pressure relief which will prevent the boom cylinders from retracting. You must either allow the flow from the power beyond port to flow back to the reservoir OR remove the power beyond fitting entirely and replace it with a standard o-ring boss plug of the correct size.

  2. #2swanson502022-07-10 21:45

    thanks for the great info. right now I just have two JCI female tube cap covering the supply and return to the auxiliary circuit. Just to confirm Jacob, I can't do that trick at the hydraulic manifold? I need to still run the supply out to the foot controlled valve and cap it there?

  3. #3jacobd2022-07-11 00:58

    It would be best not to cap it off anywhere. Right now the fluid is trying to go from the pump, through the loader valve, out the power beyond to the auxiliary foot valve, and then back to the tank. The only thing you can cap off without causing a problem are the work ports of the auxiliary valve. If you cap anything else the fluid will be constantly forced through the pressure relief port of the loader valve which will quickly overheat it and may damage the pump. But yes if for some reason you want to disable the auxiliary hydraulics you can either cap the output ports of the foot valve or replace the power beyond plug in the loader valve with a standard plug.

  4. #4swanson502022-07-27 17:48

    I hooked up the auxiliary system and the arms lower now but only if I push the left side of the auxiliary pedal down...any help would be great thanks so much!

  5. #5jacobd2022-07-28 11:26

    Sounds like you hooked the auxiliary valve up wrong. Double check the hose connections and also the linkage to make sure the valve is in neutral when your foot isn't touching it.

  6. #6gggraham2022-08-02 09:44

    I would say it may have a self leveling valve that is stuck. That can cause this symptom.

  7. #7swanson502022-08-03 18:04

    Graham, thanks for the input. Where is the self-leveling valve or part number? Again guys thanks for all the help. I checked and double checked the plumbing diagram for the hydros, and its correct from what the diagram says.

  8. #8jacobd2022-08-03 21:53

    The self leveling valve looks like this. I'm not sure where it is on an 1840 but look low down around the hydraulic reservoir and gas tank. Its pretty small and may be hidden by hoses, dirt, etc. I highly recommend just bypassing the self leveling valve. It's very easy to do and it may save you a lot of trouble. The identical one on my Case 430 ate one of its own springs for no obvious reason and sent little pieces of steel wire through the hydraulics, costing me several new hydraulic cylinders.

  9. #9gggraham2022-08-04 07:29

    The self level valve is right beside the main valve. Attached are the parts diagrams, you can eliminate this valve by hooking the hoses directly to the bucket and loader. Use the parts diagram to follow the hose routing. The bucket will not self level , if this works take the valve apart the spool may be stuck.

  10. #10swanson502022-08-07 10:50

    First off guys, thank you so much for all the help answering my questions. After a lot of searching, it appears my machine does not have the auto leveling function. That being said, what would cause my arms to not lower? they only lower if I press down on the aux left pedal.

  11. #11gggraham2022-08-08 14:40

    Possibly the spool is not stroking fully because the stem and spring have come loose or broken for the float position. I've seen the stems break and jam up. So the spool will only partially stroke

  12. #12swanson502022-08-15 20:55

    Ive taken off the loader control valve, where do I look look if the stem or spring is broken?

  13. #13gggraham2022-08-16 07:54

    See attached picture. Sometimes the stem comes loose from the valve spool and prevents it from stroking fully, or the small spring and ball in the end of the cap can jam the spool from stroking fully.

  14. #14sherwood222024-02-13 15:11

    @swansondid you figure it out? I have our case 1840 back together wasworking great for 10 minutes all controls working but then they locked up and the arms and bucket controls wont go down. Actually feel locked up. Unsure how to diag

  15. #15swanson502024-02-25 17:56

    I finally got the loader arms to lower by closing the foot operated auxiliary valve. I believe the solenoid valve was the root problem, but by excluding the auxiliary valve, it enable the loader arms to work

  16. #16sherwood222024-03-16 23:22

    This might be a stupid question - our 1840 is operated with the hand controls only. So is this control valve (picture attached) the auxiliary valve you're talking about? When you say closed it what do you mean? That valve on ours is seeping and I saw a YouTube video of another 1840 that didn't have it at all. Basically wondering why our 1840 has this valve?