Hello everyone, I am having issues with the steering gear on my grader serial number 8t15566. The steering oil is all coming out of the breather on the gear box. does anyone have the disassembly and repair procedures for this box? I have a parts manual and believe the box I have is number 2d6198. I do not have the service manual so any help would be greatly appreciated.

I took mine apart. Not too complicated. took the 6 bolt side plate off. Keep track of the shims. Cant remember how, but from there you are able to disconnect the gear rack from the piston rod. Now you can disconnect the external hydraulic tubing from the piston. Remove the piston assy. 6F5772 seals is probably bad. The small 1/8 inch tube under the box is to relieve the pressure on the other side of the piston when the piston moves in each direction. Be sure that tube is not pinched closed. ADDED COMMENT.. I don't know how to post pics, but oldmagnet probably can. the disassembles in cat serviceman book 8t1 and up Form FE030124-03 page 158 -159. basically,remove slotted screw and pin securing piston rod off the gear. The rod seal is retained with a lock ring and backed up with an o-ring.

Thank you. Looking at the breakdown in the parts book that is how I pictured it going. It is good to have confirmation I was thinking correctly. Any one else have further info on how to get the piston out of the rack before I start the teardown? Looks like a pin must be removed. Is that seal something that can be found easily at a bearing house or is it something special and needs to be purchased from cat?

I bought mine at CAT but they are only 8 miles from my house.

Thanks for your help. I replaced that seal with one from the bearing house because the local cat dealer did not have one. Luckily I ordered the correct one from cat as well. The grader worked good for about an hour then started dumping oil again. I will tear it back apart and install the seal from cat in hopes that will cure the problem. The seal removed was taller in height than the one I installed. I am thinking it may have moved in the bore and is no longer sealing aginst the oring. If this is not the case I am wondering if the seal on the valve side of the gear box could also be contributing to this problem. Has anyone had experience replacing this seal? If so any tips would be greatly appreciated. On the plus side the old girl also got a new master cylinder so it stops when you want. It also got new cutting edges and cuts much better now. And finally after about 4 or 5 years since the electric start conversion I finally got the generator to charge the 12v batteries. This old grader is the lifeline of our local dirt track, and sees a fair amount of use throughout the summer. It is definitely worthy of a little TLC. Again thanks for you help and all the knowledge I have gained reading through the info on this sight.

The 1/8 steel line under the box circulates the oil out of the piston when it is changing directions. It has to be clear. Cant remember the valve sequencing that switches direction, but that can blow your seal out. Check it closely.

Yes I checked that line when I replaced the seal a week or so ago. It was in good shape with no pinched spot. I could blow through it easily. The seal I removed did not look damaged either. That is another reason I think I may have an issue in the directional valve on the other side of the steering gear.

I have the gear box removed and torn apart. Parts will be here tomorrow. Does anyone have info on the jam nut setting for the directional spool valve on the input side of this box? Turns out I have box number 6f7772 instead of box 2d6198 if that makes a difference. Any information would be great. Anyone have a manual you could scan a couple pages out of? Thanks again.