2656-hydraulics question-draft control housing

I finally got the plate off under the seat today. Found it full of crappy looking milky fluid. Dipped out about 1 1/2 gals of hy-tran along with about a half inch of sludge on the bottom. This is the draft control housing but my industrial tractor has no draft control. Anyway I cleaned out the fluid and wiped out the sludge.

In the back of the compartment is a round changing to rectangular tube that goes up and I believe that is the oil drain. Do I really need it? I've seen in other posts where it may not be needed if we are talking about the same thing. Or should I leave it to keep sludge out of the system? The tube screws into a hole that is recessed a little lower than the rest of the housing so removing the tube would allow any sludge that collects to dump down below on the rear end. Maybe another option would be to cutoff all but an inch or so. You guys tell me.

In the front towards the right of center (looking from the rear) there is an approx 1 1/2" open hole in the casting that sits up about an 1/2" or so which is where the fluid comes in. I briefly started it to see what would happen. The fluid did not really have any pressure on it.

On the left front in the corner there is a tall hex bull plug a few inches long that is screwed in. Don't know what this does.

On the right front in the corner there is an approx 3/4" nut with a open hole and a spring under it. What is this and should I take it apart to check it?

Just behind that nut along the right side is about a 4" long flange that looks like a long rod or main bearing cap. The parts diagram calls it a hyd. diverting flange. Guess I'll open it up to see if anything is plugged. Probably hooked to it is a block on the right side of the housing by the front where the main psi line comes in from the pumps and flow divider valve and one from the loader valve assembly as well as some type of large return line from the loader/hoe which is basically held on with a hose clamp. Should I just pull this all apart and clean it?

Also on the front of the housing towards the right of center and about even with that inlet hole (in the housing) is a block where the line coming from the oil cooler is. This line is the pressure relief line coming from the power steering also. Guess I'll remove and clean it. I wan't to remove it and run it to see if it is under any psi.

I just wanted to ask here in case I do something wrong, or not do something I was supposed to before it is put back together, or just to see if someone has done this before and has some helpful advice. Thanks. Anyway I'll post back with what happened.

Fired it up and run around. Guess what? Happy days are here again. I have some steering. Was able to drive around making right and left turns. Ran the steering back and forth a number of times with the bucket down to try to work the air out. The more I drove it, the better it got.

The steering is not perfect, but at least workable. I haven't tried it with a bale on the front yet. It seems to work better when running at high revs. It won't drive with one finger like my pickup. It isn't ready for a spinner on the wheel either. It kinda drives like an old mack truck w/o power steering. I was cranking on the steering wheel with all my strength before and barely getting the front wheels to turn and now it turns well but takes a little effort.

Now I can move on to fixing some of the other stuff on this Fix Or Repair Daily IH. Thanks for all your help on this.

I pulled the hex shaped plug about 3" long in the left front corner of the draft control housing. Looks like it was just a 3/8" plug. One of the manuals mentions removing it as a drain while you are working in the housing. I'll leave it out.

I put 2 new o-rings in the flange on the right front side inside the housing. Not sure if it leaked before and was a problem or not, but it won't leak now.

I pulled the poppet relief valve in the right front corner inside the housing. This relief valve has an open hole in the top that if it is open, it will blow fluid straight up and against the top plate(when there). I saw a piece or two of metal holding the check ball open in the bottom of it. I put it in the vise to try to unscrew the top ring that holds the inner spring in place. It wouldn't budge with a screwdriver or using a hammer and chisel to try to turn it. The spring is too strong to be able to push on the ball with a screwdriver by hand. Put it in the vise lengthways with a screw pushing on the ball and got it to depress slightly with the vise. After 3 times of this, the metal pieces disappeared and the check ball is now seating. I don't know where the metal pieces went cause they didn't fall out from the check ball orifice nor did they shake out from the hole in the top. They looked like flat pieces of metal and I suppose it could be broken pieces from the spring. After the blizzard ends tomorrow, I'll shovel off the predicted 10" of snow and reinstall the check valve and fire it up to see what happens. The only problem I see with this fix is that these are all connected to the main pump running the loader and hoe which actually have been working all along unless there is some type of connection that keeps the power steering pump bypassing also. I'll post back with the results. Also it this fixes it but I have later problems with it bypassing again, I'll know just to buy a new one (without broken metal in it).

I still have to get a guage and do some psi checks but I'm not really seeing too many places where I can tie into to psi check and them some stuff is 3/8" and some is 1/2" and I think the steering lines are smaller yet and all with differing fittings which cost a few bucks a piece.

I talked to a service mgr at a different caseIH dealer yesterday when I picked up the o-rings and he said about all the power steering problems he ran into were because of a weak pump. On mine, the large pump goes into the bottom of the flow divider valve and the small pump goes into the top. They have different sizes of lines but I suppose one way to check the small pump is to cap it off and then tee off the big pump and go into the top of the flow divider to see what happens.

That overflow pipe (#19 in drawing-IH200)in the rear is a shiny steel pipe on a shiny steel rectangular plate (#14) that is bolted up from underneath the draft control housing as shown on IH-200 of the IT manual. It sits down making its own sump. I tried wrenches and you name it and it wouldn't turn at all. Upon further review of the black ring on the plate around the overflow pipe appears to be from a weld. I think the pipe is welded in unless someone thinks it is just a nipple welded under there. Anyway I couldn't budge it. I could maybe cut if off shorter with a hack saw or recip saw.

I didn't remove the hex plug in the left front, but sky you are right, the hex plug shows up in IH-202 of the IT manual as #11-drain plug. It is a small hole but I'll go ahead and remove it. Only other thing is that the overflow tube sits right above the axle and maybe it helps lube the gears or something. Hopefully someone will tell me if that makes a difference.

I couldn't pull the relief valve (#13-IH200 or #12-IH202) cause I didn't have a 1 1/8" socket with me.

I did pull that hyd. diverter flange (it doesn't show up in the IH-31 shop manual) and it basically is a connecter to allow flow between the two holes it covers. If you look at IH-200 you can see where the flange sits. There are 4 holes with 2 on the ends for bolts and 2 that flow oil. Apparently #11 cylinder and valve assembly normally bolts on there. Both of the o-rings were blown out but I don't know if it was leaking and I don't think that would fix my steering problem but I'll replace them.

I pulled the front hyd. block off the front of the case where the power steering bypass/oil cooler line comes in. Cranked the engine and it has flow.

So I'll get the new o-rings for the hyd. diverting flange, pull the hex drain plug, get a socket to check the relief valve in the housing as well as the one on the hyd. block on the right side of the housing, and then move on to another part of the hyd. system to trouble shoot the steering. I'll keep posting to keep up with the archives and onec it is fixed, I'll move this over to my old post to archive.

That about 3" long bullplug on the left front corner is not an internal drive but a long hex type nut that I can probably easily put a wrench or socket on. I'll remove it but I wonder if it might have been where the input was to the draft control valve that would usually sit in that corner according to the diagram.

I've been through the oil change before and added extra fluid before with no help. However my last oil change immediately became milky and I now suspect that the gallon and a half held in the draft control housing contributed to that. This time when I drain everything, I may add 5 gal of diesel and redrain it to help flush things. I suppose it is not a good idea to pump diesel through the hydraulics to flush them though and then end up with the hy-tran diluted by diesel. I'm still not sure what to do about the drain pipe in the rear of the draft control housing but maybe it can't hurt to take it out for a while.

The cork gasket on top of the housing is not torn anywhere so I am going to reuse that when I'm done. I also got all new bolts for the top plate and will use anti-seize on everything to avoid problems in the future.

Regarding the sluggish/virtually no power steering, I've posted on that earlier this fall. I can barely turn the wheels with no power steering and easier yet with the wheels off the ground(which suggests the hand pump may be ok). The first thing I fixed on it when I got it this summer was the top seal in the steering wheel hand pump that was flowing out all over the steering wheel and below. That didn't affect the hard steering though.

Anyway this is one of the steps I'm taking to go through the hydraulics. Then I will start pulling lines loose to see how much and with what psi the fluid moves. I suspect the main culprit is in the flow divider and pilot valves.

It appears to have both a 17 gpm and 9 gpm pump flowing into and combined at the flow divider valve which operates the loader and backhoe just fine. I still want to flow check it and also check the pressure although yesterday, I didn't see a good place where a tee would go to test it.

Another thing is that it steers better going in reverse (I do a lot of back & forth to jockey around). I've pulled a steering cylinder line to see if there is any leakby in the steering cylinder and found none leaking. The case/ih parts dept. suggested it may be the thrust bearings on the wheels are bad. I haven't check them yet and not sure how much of a job it is to pull those spindles apart but I am looking at the hydraulics first.

Never been in one of those short types, but that "long hex" plug sounds like the cushion valve. Think I'd leave that alone.

Allan