2240 Steering rebuild

[Barry Bowen]

Take a look at the third picture you have of you valve assemble. In between the two valves is the area that actuates the valve. As you turn the wheel say to the right it works to pull the shaft in the center of the valves down, and that opens the lower valve. As you turn to the left it raises the center shaft and actuates the top valves. The shims that are visible in the picture at the end of the valve that is towards the center of the assemble are what determine how much the valve is allowed to open, and that determines the flow, which determines how easy or hard the steering is. (the link for the JD page on power steering was for a 318 lawn tractor, valving is similar, but it is not an integral unit like your, it has the steering valve and a separate cylinder) You may have a piece of rubber in one of the two valves from the o-rings, try blowing out with air. It may well clear it out.

The valves look pretty well burn, meaning the steering has been in this condition for some time. The tractor having been used for that long with hot fluid is probably causing the problems with the other hydraulics on the tractor. Be sure to change out the burnt transmission fluid, and also drain the storage tank above the hydraulic pump, it will refill as soon as you start the tractor up. Change the filter from the bottom of the tractor, and besure to clean the sump screen that comes out the side of the tractor behind the regular hydraulic filter.

 

[dcyrilc]

Take a look at the third picture you have of you valve assemble. In between the two valves is the area that actuates the valve. As you turn the wheel say to the right it works to pull the shaft in the center of the valves down, and that opens the lower valve. As you turn to the left it raises the center shaft and actuates the top valves. The shims that are visible in the picture at the end of the valve that is towards the center of the assemble are what determine how much the valve is allowed to open, and that determines the flow, which determines how easy or hard the steering is. (the link for the JD page on power steering was for a 318 lawn tractor, valving is similar, but it is not an integral unit like your, it has the steering valve and a separate cylinder) You may have a piece of rubber in one of the two valves from the o-rings, try blowing out with air. It may well clear it out.

The valves look pretty well burn, meaning the steering has been in this condition for some time. The tractor having been used for that long with hot fluid is probably causing the problems with the other hydraulics on the tractor. Be sure to change out the burnt transmission fluid, and also drain the storage tank above the hydraulic pump, it will refill as soon as you start the tractor up. Change the filter from the bottom of the tractor, and besure to clean the sump screen that comes out the side of the tractor behind the regular hydraulic filter.

Already planned on doing that before I fire it back up. The only extra to what I planned is the reserve storage tank above the pump. Anything special I need to do to drain that tank beyond draining the main hydraulic tank?

 

[dcyrilc]

Well, the JD dealer stiffed me and closed early on Wednesday. When he called on Tuesday to tell me that the parts were in, I told him that I would be up Wednesday afternoon to pick them up. He never said anything about closing early. Kinda ticked me off. I have to use vacation time and leave work early to be there before closing durring the week. I waisted vacation time and an hour each way driving the 30 miles to the dealer in holiday traffic just to have to turn around and do it again next week.

At least the parts are in.

I used 120psi air to blow out the housing and valve assembly this morning. With the rubber tip on the air nozzel, I got a pretty good seal on the valve assemblies. They appear to work properly and don't seam to leak. At least not at 120psi. We'll have to see what happens after it's back together and has 2200psi on it.

 

[mattman]

I would mention the fact that you made a trip for nothing. Maybe in not so nice a manner.

Hope you get the steering fixed to your liking.

 

[dcyrilc]

I would mention the fact that you made a trip for nothing. Maybe in not so nice a manner.

Hope you get the steering fixed to your liking.

It'll come. I'm getting a chance to really understand how the system works. I'll replace anything which needs replaced and when I'm done, it should work like new! With what I'm currently replacing, the only question now will be if I have any leakage in the valve assemblies. If so, they'll get replaced.

I got the tractor cheap enough that I can afford to put a few thousand into it and I will have still got a deal on it. The only thing hurting me right now, is that I spent the extra money I had for the tractor on a used boom flail mower. It was something I had never seen for this sized tractor and don't think I'm likely to find used again anytime soon. Now I'm having to nickle and dime the repairs, but I have all winter so it's not going to really hurt me any. Just won't go as fast as I would like. Guess I'll get to work on being patient!

 

[dcyrilc]

Picked up my parts Monday night after work. The new shaft is straight where the upper seals rides on the shaft and confirms my suspicion that it had excessive wear.

I replaced all the O-rings and back up rings and began putting the steering piston back into the steering housing. I apparantly did not have the back-up ring which seals the top of the steering piston installed correctly in the bottom of the housing, because when I installed the piston, it cut three slices off the inside of the back-up ring.

I removed the piston, O-ring and damaged back-up ring (and the loose pieces). The lower seal for the piston uses the same O-ring and back-up ring so I substituted that back-up ring and reinstalled the seals into the bottom of the steering housing. I double checked the fit and then reinstalled the steering piston. Success. No pieces this time.

I've ordered a new back-up ring from the John Deere dealer ($1.45) and they have it in stock. I should pick it up Thursday or Friday.

Once I have the new back-up ring, I'll be able to install the cap on the bottom of the steering piston and reinstall the steering housing onto the tractor, reconnect the mechanical linkage, and not have the open holes in the transmission. The steering shaft can be installed after the housing is already installed.

Considering the wear on the steering shaft and that I had seen the wheels drift to the right when throttling up the tractor and not holding the steering wheel, I have decided to replace all the parts on the steering shaft except maybe the upper valve assembly. The upper valve assembly is $400. All the other parts, including the lower valve assembly, are only $200.

I'm going to order the parts when I'm there later this week. They will take about a week to come in normal freight with no extra cost and will give me time to decide if I want to replace the upper assembly also. I'm leaning that direction, but I'll wait to see how much my paycheck is next Tuesday before I make up my mind. If my check is enough, I'll just call and add it to the order. If not, I'll have to decide if I should wait a month until I can afford the extra cost or just use the old one and see how it works. I can always remove the steering shaft and valve assemblies and replace it later if need be.

I'll get and post some pix this weekend.

 

[dcyrilc]

Got the new back-up ring and got the steering piston installed. I got the steering assembly reinstalled on the tractor yesterday and got the mechanical linkage reattached. Now I'm waiting on the dealer to call and say the parts for the steering valve assembly are in.

 

[dcyrilc]

I got the parts for the steering valve assembly and got it reassembled. I installed it in the tractor today. No pix of this. The gasket for the steering shaft cover was the wrong gasket and doesn't match the cover. I had the dealer look up the gasket, and he came up with the same one that I ordered. I don't feel so bad about getting it wrong. The two options for gaskets are noted as: 1-(C)Hi/LO or 2-(A)Reverser; (D)less Hi/Lo. As my tractor doesn't have either Hi/Lo or Reverser, we both chose option 2. Upon further investigation, I discovered that the covers have the same choices available and my cover has the part # L41719JD on the inside of it (see picture). The cover listed for option (C)Hi/Lo, also has a note stating "(C) (SUB FOR AL30173) (SUB L41719 AND L64255)". Although I don't have a Hi/Lo transmission, I think I'll check the Hi/Lo gasket since my cover part # is listed for that unit. I see another trip to Deere in my near future.

 

[dcyrilc]

I was right, it was the other gasket. I'll get the cover on this weekend and see if I can fire it up and test the steering. I currenly have the cowl which contains the batteries and all the ignition wiring removed to rebuild it while the tractor is down. The bottom of it was rusted out. Because of this, I'll have to get creative for hooking up wiring to start it. I want to move it outside the shop to pressure wash the area under and in front of the cowl while its off. Should make for some interesting pix with the wiring piled up infront of the steering housing.

 

[dcyrilc]

I got the cover reinstalled today. I've decided to wait to fire it up until I can replace the hydraulic fluid. I checked the fluid and it was nasty. My next step will be to continue rebuilding the dash/cowl/battery area which I have been documenting in this post: http://www.tractorbynet.com/forums/customization/157588-rhino-lining-battery-area.html

The documentation will continue in that post.