VAC

• Case VA

Other oil required is in the torque tube, factory oil was 5W,10W or 20W engine oil pending ambient temps. Capacity is 2 gals. General purpose hydraulic oil or 10-30 motor oil is often used.

Steering gear box requires SAE 140 gear oil or grease pending model year, wfe, or nfe.

And of course, engine crankcase and air intake oil cup.

There are several reasons for the eagle hitch problem. The control valve may be stuck or spring broken, release valve not actuating, lash not set properly on either of those valves or the actuator is broken, cylinder scored with leather cup hung on earlier models, return oil restricted possibly by filter but more likely by the release valve or tubing.

You'll have to provide more info to figure out your problem. With the engine off, lever in the down position can you push the draft arms down? If so, do they raise again when you start the engine with the lever in the neutral position.

When you grease the rock shaft, the grease accumulates under the piston and is pushed back to the torque tube along with any leak-by oil via the 5/16" tubing on the lower right side of the rock shaft housing. If this tube becomes plugged with hard grease there will be an air lock under the piston and the draft arms will not drop under there own weight but can be pushed down by hand in most cases.

The ebay manual cited is too old for your tractor, dated 8-48, won't cover eagle hitch or other changes 49 & later.

Joe

In Reply to: Case VAC Eagle Hitch posted by Tim Campbell on October 20, 2003 at 13:13:03:

Hi Tim,

There four valves in the control block:

(A) lift valve aka pressure control valve.
(B) lift check valve.
(C) release valve.
(D) relief valve.

(1) When the engine is running with lever in neutral position the pump circulates the oil in the system and back to the torque tube via (A). (B), (C) & (D) are closed. Pump press is only that required to overcome friction to oil flow through the open system (guessing less than 10 psi).

(2) Lever moved to raise position closes (A), pump press builds up overcoming spring on (B) admitting oil to piston. Pump press continues to rise to overcome weight on draft arms up to the 800-900 psi setting of (D).

(3) With draft arms lifted, lever moved to neutral, a spring opens (A), press differential and a spring close (B). (C) & (D) remain closed. System is back to (1) above with pump circulating oil. Oil on the piston is in a hydraulic lock due to closed (B), (C), & (D). Oil press on the piston will be only that generated by the weight on the draft arms.

(4) Lever moved to lower position opens (C) dumping trapped oil on the piston back to the sump and draft arms drop. (A) is still open, (B) & (D) remain closed.

((This portion applies to the original post, Sam))
The draft arms can only lift when you start the engine and the lever is in neutral position when the return to the sump is restricted or blocked. Since your draft arms will drop when the lever is moved to the lower position, that block can only be (A) stuck closed and or the spring is broken. You have probably been operating the pump at full pressure circulating oil only when the pressure opened (D) at 800-900 psi with the same constant pressure on the piston. When you put the lever in the lower position, (C) opened and the pump simply did not have enough capacity to overcome the pressure drop plus the weight of/on the draft arms.

So now that it won�t lift at all it is possible that the pump is shot (or shaft key sheared?) from running up against relief pressure nearly 100% of the time (doubtful). (D) is now leaking and/or spring is broken (maybe). (C) is now stuck open and/or spring is broken (likely). Or a combination of above.

The are many reasons for a hitch that is operating normally to stop working I.E. sump low or dry, air being sucked into the pump, depth control lever or pin broken, lash setting screw(s) loose/backed off, etc, etc, etc.

You have been operating with one problem and have now developed an additional problem. There is no doubt that your lift valve is stuck closed and/or spring is broken. It is likely now that the release valve is stuck open and/or spring is broken.

Sorry for the long post, I am just too dumb to figure out a way to shorten it and get the point across. Joe

ebay # 7614711381