# David Brown 990



## Looking for help (Jan 23, 2020)

I am trying to find out why 3 point hitch will not lift . It was going up and down when i decided to change oil that was contaminated with water .Flushed system a couple of times .New oil and filter.Now will not lift.Its a David Brown 990 serial nu 9901862839


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## John Palmer (Mar 11, 2019)

The control valve within the rear axle housing needs to be removed and the valves cleaned. It is an animal. You can first try removing the plate over top the control valve that sits in between the selector switch and the main lift control arm. You'll see two large valve covers. The one closest to the driver's seat is the "hold valve" and the one closes to the right tire is the "by-pass valve." Its a son of a gun, but if you remove those two valves and clean them and it works, it beats the heck out of removing the entire control valve from the axle housing.


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