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cat 320 b excavator

rankothge ยท 2013-09-09 06:58

cat 320 b excavator heat up within 4 hours. i think engine is OK. hydraulics cooler is OK. filters & oil condition is good.i have met several cat 320b, 312b excavator this issue. anyone know any hydraulics defective that machine have? thanks

Replies16
  1. #1Per Eriksson2013-09-09 16:10

    It's the hydraulics that gets hot? Reseal swivel, check main relief pressures and all line reliefs too.

  2. #2George catman2013-09-10 06:25

    Evening, We have a cat 320b (long carriage) with the same problem,it has 10,400hrs, we have replaced radiator core, water pump, thermostat, tighten belts, checked external condition of hyd cooler and is in top shape, replaced check valve cartridge in hyd oil cooler line to ensure it was not relieving to tank with out cooling, would worn hyd pump cause this with excessive leakage? Or would rotary valve cause oil to get so hot? The operators have complained in recent times about it not walking as well as it could? At a stand still on where to head next. Any input would be great from some cat experts Cheers

  3. #3Nige2013-09-10 07:08

    You've answered your own question. Not walking "as well as it should" but with no hydraulic complaints other than that for my money points directly to the swivel needing resealing.

  4. #4Cmark2013-09-10 08:36

    Check all the foam rubber seals 'twixt the radiator pack and the frame/bonnet. They stop the fan recirculating the hot air through the radiator. I'll bet you a pound to a pinch of chinese excrement that they're missing.

  5. #5Per Eriksson2013-09-10 14:39

    Have to agree with Nige, do the swivel, it's the prime suspect when it comes to weak tracking and overheating hydraulics. Cheap and easy to do also compared to messing with pumps and valves.

  6. #6digsalot2013-09-11 21:32

    Swivel? Can anyone comment on the process of resealing a swivel? Thanks!

  7. #7Steve 6502013-09-11 21:57

    swivel, check all lines relief, check and adjust the main relief, check for the proper belt routine to ensure its correct. bad belt routine makes the fan revolution at lower speed without the common slippage sound, its easy to put the belt in the wrong way and think its ok. already saw this!

  8. #8ih1002013-09-14 15:53

    If you track back from the hyd oil cooler, one hose goes into a block containing a diverter valve, if I remember right. Might pay to have a look at this. Are the strainers in the tank clear?

  9. #9Nige2013-09-14 16:16

    Are you asking about the swivel on a Cat machine or is it a "generic" question..? If it's a Cat machine then PM me the Serial Number plus your e-mail address and I'll happily fire off a copy of the relevant procedure. Anything other than Cat then I suggest you start a specfic thread for the machine in question.

  10. #10rankothge2013-09-16 06:39

    yes you are correct Mr. cmark. i am also find that issue good luck

  11. #11rankothge2013-09-16 06:47

    no swivel is ok. i find its issue, heated air recirculate through the cooler thanks all to reply me good luck

  12. #12Nige2013-09-16 07:12

    Score another one for the old codgers ............:thumbsup :thumbsup

  13. #13Cmark2013-09-16 20:02

    Glad you got it fixed.

  14. #14ih1002013-09-17 06:18

    I'm pleased it was that easy.

  15. #15Nige2013-09-17 10:03

    As per the oft-quoted saying. "When you're up to your *** in alligators it's often difficult to remind yourself that the original objective was to drain the swamp" ......... how true.

  16. #16cepick2013-09-22 05:11

    Cool