In Reply to: Very weak hydraulic lift ford naa golden jubilee posted by Francois Cote on May 07, 2019 at 07:02:36:
That is the unloader valve. Put the nut back on and leave it alone until you understand how it works and what it does. The over pressure relief valve is in the bottom of the center section case. You have to split the tractor to service it. The most common cause of weak lift is worn pump or leaking lift cylinder. You need to read the shop manual and understand the operation of the 3pt lift system if you are going to work on it.