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JD 444D Brake Question

beauganas ยท 2024-03-31 23:49

Hey guys, I'm back again. I got the loader moving (thanks to you guys)...but now she won't stop. John Deere 444D Serial DW444DB509098 TM-1341 is the repair manual PC2059 is the parts catalog Loader brakes, which previously worked before new hydraulic pump, new brake pump, etc. do not work now at all. I undid the right brake bleed screw on the front differential today to bleed the brakes and no oil. I basically have the screw hanging in by a thread, wife on the brakes...no oil. 1. Trans oil is about 3/4 of the way on the dip stick between low/high at low idle. 2. A new brake accumulator was installed as part of the repairs I did while the new pump was being made. Brand new, from Deere ($3k walking out the door, painfully ridiculous). 3. I had a new brake filter installed as well while servicing the machine. 4. I believe I have some brake pads left to slow it down (see attached photos) 5. I have changed the oil in both front and rear differentials (I don't THINK that affects brakes, but in case it does). What diagnostics should I be thinking about? Any other information needed? Appreciate the help, BSG

Replies6
  1. #1mg23612024-04-01 05:58

    Need to check both the brake system pressure and the unloading valve pressure. Is your TM1341 the repair manual or the operation and test manual? The TM1341OP will have all the diagnostics in it. The TM1341RE is tear down and assembly only.

  2. #2Diesel Dave2024-04-01 13:21

    What was found in the brake filter housing ? Was the end of the brake filter cone blown out ? That brake hydraulic system does not like any kind of debris at all. Like mg2361 said you need to check the brake system pressure and the unloading valve pressure.

  3. #3beauganas2024-04-01 16:30

    Hi Diesel Dave, I can't confirm; the JD Mechanic replaced it while I was tinkering on something else. He made no specific mention of debris, etc. No, brake filter cone was intact. I'm studying up to do these tests; I'll report back my findings...it may be a few days as I need to get a pressure transducer delivered. Thanks for the help, BSG

  4. #4beauganas2024-04-01 16:52

    Hi mg2361, Both the 'Loader Operation and Tests' and 'Loader Repair' manuals are given the TM-1341 numbering (at least my versions I bought online do).

  5. #5mg23612024-04-02 05:00

    Then go into the Powertrain section of the Operation and Test manual, subsection Tests, and in there look for the Unloading Valve Pressure Test. Both the unloading valve and brake pressure procedures are in there.

  6. #6beauganas2024-06-16 19:55

    SO...closing the loop on this. Total brake system rebuild was required. Unloader valve, brake valve, missing warm up check valve, brake pump had some internals reversed, new pads, seals were bad so they got replaced. New parking brake pads put on. Engine timed. Ended up taking to JRE in Asheville. Not cheap, but she stops on a dime now.