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310 SE Hydraulic problem

kemoreser · 2022-10-02 21:53

I'm working on a 310 SE. Front loader and outriggers won't operate. Backhoe and power steering work. Priority valve gets hot.Pulled spool from priority valve and checked. Didn't see any problem. Any ideas?

Replies9
  1. #1boone2022-10-03 17:33

    The experts are going to need the serial number. Sounds like your system relief valve which is in the loader priority valve section is dumping pressure. Steering will get priority and then it goes to the loader, stabilizer and backhoe functions. Your backhoe is probably working cause it's an SE and has an auxiliary pump to power it. I'm guessing you don't have full power to the hoe.

  2. #2kemoreser2022-10-03 22:00

    Serial# is T0310SE840818. The hydraulic system is under load when nothing is being operated. Would that be happening if the system relief valve is dumping pressure?

  3. #3mg23612022-10-04 05:19

    Your serial indicates an early machine which should have a removable orifice in the priority spool. Did you check the orifice in the center of your priority spool? Is it missing? Should be a .030"-.040" hole in the spool. If the orifice is missing, it will be approximately an 1/8" hole. If it is missing, it will cause your issue.

  4. #4kemoreser2022-10-04 11:13

    I didn’t see a removable orifice or a place for one but the hole in the center of the spool looked to be bigger than .030 or .040. I thought that was the orifice.

  5. #5mg23612022-10-04 12:10

    If you have a drill index, see what size drill fits. Post result.

  6. #6kemoreser2022-10-04 12:53

    I’m not near the tractor today. It will probably be tomorrow before I’m back there. Thanks

  7. #7kemoreser2022-10-06 17:04

    I pulled the spool again today and the hole through the center is 1/8 “. I can’t see a place for an orifice to be installed. I started the tractor just to check operation before I pulled the spool and front bucket and outriggers worked fine for a minute or two at idle then it was right back to same problem. Relief valve on upper end of priority valve started getting hot.

  8. #8mg23612022-10-07 05:17

    That hole needs to be .030". Anything bigger and it is an issue with loading the hydraulics in neutral. The only fix is a new priority section. The only other issue that can cause load in neutral would the load sense orifice in the steering valve. Remove the load sense fitting in the steering valve and inspect the orifice for debris.

  9. #9kemoreser2022-10-07 11:18

    Thanks, I will check the steering valve next.