[Jack Houpe]

I have cylinders on our John Deere that have been sitting outside in the snow, rain and burning hot sun for years and still don't leak. Why are these slide cylinders leaking? Is the oil that is eating up the seals? Are they that poor of quality?

[Gnawrocki1]

I think it is just like the rest of us.....old age.  There is no rust, at least on the ones I have seen.

[Latitude 28]

I have had cylinders in the most difficult environments that never leaked and have wondered the same thing. If you look at the end of my cylinder you can see the wiper seal deteriorated.  That seal has no pressure on it at all....pressure is retained by the "loaded U-seal" an inch or so inside the block.  The wiper seal came out in tiny chunks of rubber and in fact stained my rag black indicating a degrading rubber.  All the other HWH components i have rebuilt were in the same condition when they leaked.  It would take a chemist to analyze what is going on.  I do know this from distant past experience "brake fluid" and "mineral based" hydraulic fluids ARE NOT COMPATIBLE.  If someone put brake fluid in the HWH system thinking that was okay it would cause what we are seeing.

[Jack Houpe]

Steve all my tractors and forklift use standard cheap hydraulic fluid which is why I brought it up but I'm putting power steering fluid in the HWH I guess because they are worried about temp and viscosity during compression. I do remember aircraft hydraulic fluid, which is NASTY stuff.

Glenn yes I am old.

[Latitude 28]

Like Russ stated above, i dreaded the day if my salon's front cylinder ever started leaking.....well it developed a leak.  I read, with great interest, Glen's write-up about his cylinder rebuild/replacement and removed it from the coach.  I had made up an opposing V-blocks when I rebuilt the aft salon cylinder last year https://newellgurus.com/showthread.php?t...D+cylinder, post #5 to hold the cylinder.  Used them again, wrapping the cylinder with some rubber backed carpet and with a big crescent wrench to remove the square block on the end....worked great. 

This is a follow-up to my leaking front HWH hydraulic cylinder rebuild and Glen's posting.


Removing and reinstalling the front cylinder seemed impossible through the tiny access hole in the passenger wheel well. Following Glen's instructions, https://newellgurus.com/showthread.php?t...D+cylinder.... thanks Glen!  I poked around the driver's wheel well a bit and found the access plate for the rod end attachment countersunk machine screw.


I will try to articulate what worked for me in the following write up:


Preparation:

• Raise the coach as far as you can.
  
• Jack driver side remove the driver side front wheel.
  
• Support with cribbing both sides of coach.
  
• Remove access plate, just above the air bag buried in the insulation on driver side wheel well.
  
• Remove access plate Passenger wheel well.
  

Remove Hydraulic Cylinder:

• Start with the slide retracted. Extend slide to almost fully extended and stop short of the locks engaging and the floor coming up. Doing this keeps the stop switch from being activated and allows the system to retract and extend the cylinder without the floor and lock sequence having to operate. Could be other ways to do this I just know it worked for me.
  
• Gain access to the salon's aft cylinder. Mark both lines, disconnect, cap and plug both lines also cap the cylinder tighten all caps and plugs. A small catch bucket and rags are in order here. You could open the cylinder HWH solenoids on the HWH manifold....I would rather know what IS or IS NOT going to move by disconnecting the cylinder.
  
• Driver's wheel well, remove the countersunk machine screw viable through the access hole above the air bag.
  
• Turn on the HWH system and retract the salon's slide The front cylinder will be the “ONLY” item moving. You will hear the pump change tone when fully retracted. Turn off HWH system. Side note...there is a rectangle steel tube attached to and moves with the slide as the cylinder extends and retracts. The end of the cylinder's rectangle block resides inside this tube. With the slide almost extended, the cylinder's rectangle block is just before peaking out of that rectangle tube.
  
• During the above operation nothing should move as far as the slide is concerned except the mechanically disconnected front cylinder.
  
• For the ease of description, I am going to use “forward” will be the nose direction of the coach ”aft” will be the tail direction, “left” will be the coach driver's side direction and “right” will be the coach passenger's direction.
  
• With the cylinder retracted, mark the hydraulic lines, disconnect, cap and plug the cylinder and lines. Again a catch bucket and rags are needed here.
  
• Remove the large nut from the threaded boss of the cylinder being careful not to disturb the inboard adjustment nut.
  
• Slide the cylinder inboard towards the coach “left” clearing the mount bracket.
  
• Shift the cylinder end to allow you to slide the cylinder towards the coach “right” direction....you will hear a thunk inside the coach....that is the cylinder falling clear of the slide's rectangle tube.
  
• See the attached picture, “first operation” Move the rectangle end of the cylinder “aft” about 15 degrees. Grab the threaded end of the cylinder and rotate 180 degrees. You want the cylinder's fittings to face right as you look at the end.
  
• “second operation” with the threaded boss outside of the hole pull the cylinder's end towards the outboard direction. This clears the structure inside the coach to allow the next steps.
  
• Now swing the cylinder towards the “aft” end of the coach and start working it out of the hole a little at a time.
  
• Once you're ready to go back in it's a reverse of the above with a couple of hints.
  
• Make sure the hole on the rod end is perpendicular to the cylinder's rectangle block or you will be taking it back out....don't ask how I know.
  
• Refer to the picture....keep the threaded boss out of the hole till you clear the internal structure then you can start with trying to line it up with the rectangle slide tube.
  
• Once you are back to the 15 degree angle you now can rotate the threaded end of the clockwise in order to place the hydraulic lines aft back in original alignment.
  
• Once you are close to being in alignment then you can then slide the cylinder inside the hole.
  
• Bring the threaded boss outboard as far as you can. This is where Glen had some trouble getting the cylinder's rectangle block inside the tube. I placed a block of wood 1.5”x1.5”x6 as far as I could reach under the cylinder for a fulcrum point. With a bright light and mirror look towards the slide rectangle tube. Align the cylinder and tube as best as you can. Pull the threaded boss end of the cylinder down and slide the complete cylinder inboard till it stops. If you're lucky it'll go in most likely the cylinder's block is hitting the rectangle tube....that is a good thing as the protruding rod end will give you and idea where the center of the tube is both fore and aft as well as up and down by using your fulcrum. When it lines up it will allow you to put the threaded end back into the mounting boss. Install the nut loosely so as it won't fall out you will need some play to assist you lining up the rod end.
  
• Re-attach the hydraulic lines to ONLY the front cylinder.
  
• Two people will be handy for this. Turn the HWH slide system on and extend the cylinder to align the rod end and install the countersunk machine screw on the “left” side of the coach.
  
• Tighten the large nut and re-attach the rear hydraulic lines.
  
• Operate the slide by retracting completely and then extend fully....things should work normally as the HWH system is self bleeding.