# NAA hydraulics



## loafersglory (Apr 11, 2009)

I have a Ford Golden Jubilee tractor. Recently I rebuilt the 3 point hydraulics. Tested after installation everything was working properly until the unit ceased to lift. Hydraulic pressure had tanked (was 1200 - 1500 PSI) at plug on top of unit. A visual inspection revealed fluid leaking from safety/relief valve on piston lift cylinder. I replaced valve and now have no pressure on gauge. I want to know if I have the proper replacement part (see photos)? The shaft end of the new valve is beveled where the shaft the old one is concave. Does the check ball have to be removed to use new valve? Any information would be appreciated. Thanks


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## BigT (Sep 15, 2014)

Hello Loafersglory,

Welcome to the tractor forum.

I checked ebay for the safety valves in question, and found both types on sale there. *Same* part number. 

The "new" safety valve is P/N 8N638, and is for a NAA, Jubilee, 2N, 8N, 9N. 
The "old" safety valve is P/N 8N638, and is for a 2N, 8N, 9N. 

You must have a blockage in the hydraulic system somewhere, if the safety valve popped off. The hydraulic pump may be damaged.


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