No 44 Hydraulic seal leaking

The input shaft from the motor into the pump or the control shaft on top of the pump?

Sorry..should have been more specific. The control shaft on top. The picture shows where I am now in putting it back together and before I go much further I think I should fix the problem. There appears to be a washer riding in a groove under the control arm.

There should be a lip seal. Actually a pair under the linkage arm. I had to pull the front cover off and remove the entire shaft. Maybe there is a better way? I measured the shaft and bore and ordered a pair of seals thru Motion Industries. Do not have that info anymore. Maybe available thru Cat yet.
You do want them in good shape, not only lets oil out, but contaminants in.

Matt

Bill, I cut and pasted my reply from a post on ACME. Here it is:

[i]I had to replace the exact seal on my #44 mounted on my D4. I had the same problem as you do. To replace the seal, you will have to drain the hydraulic oil resevoir and remove the front cover. I do not remember the exact sequence, but you will have to dis-connect the internal linkage that runs from the shaft to the spool. I do remember there was one internal capscrew that just barely gets in the way of removal, so you will have to pull the bolt completely out. There are some keys that you won't want to loose, so keep a magnet handy. The shaft on my #44 was pitted from rain water collecting on top of the seal. After installing the 1st seal, it still leaked badly, so I had to go through the entire process again to stack a second seal atop the first. There is enough room to do so. I would suggest doubling up on the seal so you don't have to do the job twice. The part is a standard Chicago Rawhide seal. If I remember, I will look for it tomorrow and reply. Good luck.

The Chicago Rawhide seal number for my hydraulic shaft repair is 11223. I believe I paid about $4 each (I bought 5 "just in case").[/i]

Good luck on the repair. P.S. you may have water in the system if your shaft was pitted from water, in which case you will need to flush the system a few times.

Thanks for the information B4D2 and SpragueM. I was hoping not to take the front cover off but see I will have to now.I have all the lines off so the only fluid left is in the tank. Do I need to remove the unit from the D2 or can I leave it attached and fix it ?Also when I remove the cover I am assuming there is a gasket that will probably need replacing. Where can I get that gasket ?

Thanks again......Bill
T

Pitted control shaft can be recovered using speedy sleeves.
Unit does not need to be removed unless you are replacing the drive shaft seal (which it probably needs also).

When reassembling the control shaft be sure to set the vertical position so the detent roller is centered. (may require changing the shim washer under the lever)

The cover gasket is available from Cat.

Thanks for th info OM....does anyone have a good source for the hydraulic filters.

I finally found a source for Cat parts and they have been really helpful. I ordered the Hydraulic filter, cover gasket and the shaft seals plus several fuel filters and related gaskets. All came to the door without a problem and the price was reasonable.
I removed the shaft and did I get a surprise. The original seal was still there but apparently it was bad and the previous owner stacked O rings on top to slow the leak down. It worked for a while.The shaft is pitted, rusty, though not terribly bad and I guess either a Speedi-sleeve as suggested by OM or have a shaft made. Don't know which would be better. Any suggestions ?

Check the shaft bushing wear before you make the decision to replace or repair.
Might also check with Cat for replacement. I was able to get the smaller inner shaft for the two valve #44 not long ago.