Case 430 leaking hydrolic fluid

[Chrismc19]

I have a Case 430 Diesel 1967. It leaks hydrolic fluid between rockshaft housing and Draft arm. Don't see hydrodlic fluid in gear oil (dipstick just in front of seat).
I have viewed videos of piston being rebuilt but just trying to understand the path of the leaking hydrolic fluid to further fix the problem.
Also, when lifting an implement, it raises then drops slightly and then lifts back up.
Chris

 

[chuck machinist]

Am I to understand you have two different weight oil?s one in
your differential and one in your torque tube? As I understand
it but the two should be the same. You and I struggle with the
same issue . I have been scouring the archives, and
speaking with others with great knowledge of this issue. My
first plan of attack is to replace the seal and wiper on the rock
shaftPiston. I?ll be getting into mine this week. We have to
start somewhere and I believe the rock shaft piston seal is a
good place to start.CMMy email is open

 

[bradley martin]

The 2 most common paths of migration of the oil from the transmission to the rear end is either seal failure on the rock shaft piston OR seal
failure on the PTO shaft where it passes through both compartments. You can determine which is causing your issue by hitching to a 3 point
implement ( plow, bushog, etc) and leaving it in the raised position overnight. If the implement has settled down overnight, the rockshaft
cylinder is the culprit. If not, it will be the PTO seal. Replacement of either will require removal of the seat assembly and the " lid) for the
rearend housing.

 

[Bruce from Can.]

Several years back, I had a 530 Diesel Triple
Range, fantastic tractor, but it had hydraulic issues
too. Hydraulic oil would migrate from the torque
tube/oil reservoir into the rear end, and run out axle
seals. We eventually had to split the tractor and
replace the seal on the shaft that runs through the
torque tube. Parts are not very expensive, but a lot
of labour involved. Once my little tractor was fixed,
the 3 point hitch work perfectly.

 

[Case Nutty 1660]

Leaking piston seal cause the drop and then to be picked back up, depending how fast it is it can be not a huge problem, I am guessing you are getting oil out of the rockshaft area, that requires pulling the top cover unit and doing a complete reseal and check over,, your hyd oil is in the torque tube area and does not come from the rearend/transmission, the check fill plug big hex top like the rear end check/fill) should be on the RH side under the fuel tank, depending on what year your 430 is, it can also be on the LH side and is a square headed pipe plug with dipstick
cnt

 

[John Saeli]

Chuck: The best test of the rockshaft piston is to raise the 3 pt hitch, best if w/ a load, shut the engine off & leave overnite. If the arms drop, the piston seals need replacing. Yes, 2 different oils are required, Transmission-Hyd (Hytran) in the Torque Tube section, and 85W 140 in the tranny-diff.

 

[chuck machinist]

I appreciate the clarification on the fluids John. I took the 430 for a shake down run after replacing the seal and wipers in the steering cylinders, as well as the power steering pump filter you provided me . Thank You!CM

 

[Chrismc19]

(quoted from post at 04:49:11 05/13/19) Leaking piston seal cause the drop and then to be picked back up, depending how fast it is it can be not a huge problem, I am guessing you are getting oil out of the rockshaft area, that requires pulling the top cover unit and doing a complete reseal and check over,, your hyd oil is in the torque tube area and does not come from the rearend/transmission, the check fill plug big hex top like the rear end check/fill) should be on the RH side under the fuel tank, depending on what year your 430 is, it can also be on the LH side and is a square headed pipe plug with dipstick
cnt

Thank you- (and others) for the quick response.
I will check everything everyone suggested.
Chris