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Steering wheel and clutch pedal not working in the first engine start of the day.

Southbus ยท 2023-04-17 12:24

Hello everyone, here I am again looking for help to solve a problem with my Champion 720R year 1988, serial number 720-187-134-19089-88. On some occasions, to turn on the machine I cannot move the steering wheel or press the clutch, both are very hard and I think they have no hydraulic pressure, sometimes I have to wait 20 or 30 minutes, with the engine running, to get those functions back . I think that perhaps there is a problem with the pump or some device that does not allow the passage of oil to these controls. The hydraulic oil level is correct and the filter has about 200 hours. This happens on the first ride of the day and all the other hydraulic functions of the machine work without problems. Can you give me any advice to start this new repair adventure? thank you so much

Replies8
  1. #1Tones2023-04-17 18:37

    When it's cold pressure test the pump so you have a bench mark then test all outlets on the control bank. Worn or broken 0 rings can be the cause which then causes internal leakage.

  2. #2Southbus2023-04-17 23:36

    I forgot to mention that the fault suddenly disappears and the steering and clutch work one hundred percent again. This fault does not occur every day, on some occasions I turn the engine on and the fault does not occur, but on those occasions, just after starting the engine, I hear a noise behind the cabin, like air being released or hydraulic oil flowing quickly. It's hard for me to describe that brief sound after successful ignitions.

  3. #3cuttin edge2023-04-18 19:44

    Does that machine have the belt driven pump

  4. #4Welder Dave2023-04-19 23:42

    Did it do it before the filter change?

  5. #5Southbus2023-04-20 06:07

    Hi Welder, Yes!

  6. #6Southbus2023-04-20 06:08

    Cuttin edge, it no have belt drive.

  7. #7Southbus2023-04-20 06:16

    I think @Tones is right, today in the morning the problem arose again and while the engine was running I released one of the outputs of the rear hydraulic pump (steering, clutch and transmission pump), and many bubbles escaped, then The hydraulic oil came and at the same time he felt a change in the sound of the engine... The pump began to work, then the clutch and steering work correctly. Clearly the pump is sucking air from somewhere, although the hose coming from the tank looks fine, but the body has some oil leaks at the rear, where there are a couple of big plugs like nuts. There must be the origin of the failure. Now I need information and advice on how to restore that pump, will it be a matter of just disassembling, changing o-rings, cleaning and reassembling? Maybe someone on this forum has disarmed this pump.

  8. #8Tones2023-04-20 14:27

    The hydraulic pump could be OK if it working properly once the air is bleed out. It only takes a pin hole in any part of the suction hose/fittings to allow air in. Things like the tank strainer should be checked also.