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Cat 311CU slow and weak

RobVG ยท 2009-12-30 12:39

Opperators let me know this machine is having issues. I'ts rarely used anymore. Evidently it use to be scary fast on the swing- now it's slow. They say it's also slow on the boom up and down and weak on the stick when grading. Haven't had a chance to look at it yet. Does that sound like bad relief? If it is, I don't have a clue as to what/where it would be- no manual. Do each of these functions have their own reliefs or is there some type of system relief that would cause all the problems? I could test pressures with a gauge but would have to make up adapters. Any ideas?

Replies4
  1. #1nzpatch2009-12-30 15:18

    i had the pump rack thing come loose on my 311cu and the digger lost power in sum funtions and tryed to stall if you kept pulling ,one track walked fast too. put the adjuster back to the right spot and all good.

  2. #2dayexco2009-12-30 19:42

    aw come on...it has a CAT decal on it, doesn't it? they don't break down, they don't give grief, they're the cheapest per hour to own, aren't they? just crawl back up in the cab, pull the key out of the ignition, count to 10, put it back in....and it's just like windows on a PC....it'll reboot!!! you're good to go

  3. #3John C.2009-12-30 19:47

    You can check pressures right on the monitor pad if someone knows how to get in. PM me and I can walk you through the process. The quick couplers are available at any Parker fitting store. I get mine locally at American Hose & Fitting. How many hours are on this beast? Is it domestic or gray iron?

  4. #4RobVG2009-12-31 13:10

    It's gray market. 6500 hrs Thanks for the offer John. I'll send you a PM probably tomorrow. Happy new year! ---Funny story, sent it out for new tracks/idlers a few years back. The poor guy had a hell of a time getting one of the idlers out. Unbeknownst to me, the machine had fallen off a moving railcar and needless to say the frame was bent...