1970 JD 300 Loader - Hydraulic leaks

[rortiz]

This is the 1St tractor ever owned. I just replaced a hydraulic hose (to power steering I believe).. Now I have 2 additional leaks coming from the housing unit (name unknown) to the right of where the battery is located on this tractor. This unit has about 5 hydraulic hoses attached to it. See attached picture. This housing has 2 round caps the size of a quarter. Fluid is leaking from the base of these 2 caps. Could it be due to air in the system? Can these caps be removed and repaired? If so, how are they removed? See the close up picture showing these 2 caps. Does the entire housing have to be removed? What is this unit called? Also, how does one remove the air from the hydraulic system? I also plan to replace the other hoses that are showing signs of cracking. Hope some one out there can help. Thank you.

 

[Tx Jim]

Air can be purged from hyd system by cycling all hyd control functions several times. The item in your photo is a 2 spool hyd control valve. Here's the repair parts if the valve is original.
4-P46051 O-Ring View/Update 1.07 USD 4.28 USD
4-T30942 O-Ring View/Update 4.03 USD 16.12 USD
2-U15192 O-Ring View/Update 0.92 USD 1.84 USD

 

[rortiz]

Jim,
Thank you for your quick response and and parts info. My first time using a forum and am really impressed on how freely and quickly valuable information is given. Again, thank u. One add'll question, how do I remove and replace the caps without damaging them? I know I'll have to remove the hoses first, which I plan to replace in order to get to the caps.
Gratefully,
Rob

 

[Tx Jim]

Actually the hoses can remain in place to remove the caps. one cap just screws off and the other I'll have to study.

 

[rortiz]

I don't know if you can see the caps in the picture, they are both the same size, perfectly round and smooth on top with no slots for a screw driver. I Don're see them on the schematic which you you thoughtfully attached. Forgive me if I am making this more difficult than it soul be. I appreciate your help and time. Thank u.

 

[Tx Jim]

Sorry but my feeble eyes can't distinguish the caps you refer to. The valve in the schematic I posted was for an original valve that was on loader 43 years ago. Some caps are retained with only a snap-ring