HELP please 3121RL slide hydraulic total failure

[ChuckS]

From my fifth wheel,showing how the slide cylinders are attached to the frame bracket under the coroplast covering

[scott802]

hi Chuck,
The video is super helpful that you have. Thanks very much for that.
At this point I'm stuck with basically just manually cranking with a wrench.
I haven't been able to remove the underbelly yet but I am pretty sure that cylinder is just free floating because I literally heard it break off at one end.

Is there a part that needs to be ordered or do you basically have to replace the entire cylinder with the piston etc?

Once I'm able to open it up i will get photos

[ChuckS]

Originally Posted by scott802

hi Chuck,
The video is super helpful that you have. Thanks very much for that.
At this point I'm stuck with basically just manually cranking with a wrench.
I haven't been able to remove the underbelly yet but I am pretty sure that cylinder is just free floating because I literally heard it break off at one end.

Is there a part that needs to be ordered or do you basically have to replace the entire cylinder with the piston etc?

Once I'm able to open it up i will get photos

Until you gain access to see what happened you won’t know what is needed.. it could simple be the nuts came loose and let the end of the actuator loose and it would have made a heck of a noise if it came loose under pressure

The bracket that is attached to the frame that is used to hold the rod end may have come loose ( not likely )

The rod end could have broken off the cylinder.. (not likely)

My bet is the nuts came off..and even though it is double nutted ( one serves a a lock nut for the other ) I have seen them come loose

The hydrauilc line that blew can be locally made any any NAPA store that builds hydraulic hoses … standard JIC37 fittings (1/4 inch ID) 9/16 OD hose

[Mikendebbie]

Here is another view of the anchor brackets ChuckS mentioned that the slide hydraulic cylinders bolt to. These are the points that you can't see because of the coroplast+radiant barrier covering the underside of the RV.

Location "A" and "B". In this screen shot from a factory tour video - the cylinders have not yet been installed

[scott802]

Hey all,
thanks so much for all your help and advice. I'm having difficulty getting the underbelly exposed because the tech that worked on it last time stripped the threads on one of the bolts. BUT, I did manage to expose the lines and take 2 photos. There is almost like a 'T' connection it looks like that got stripped (threads look stripped) and this came right out of the piston?
I might be mistaken but these photos should help with next steps.

[BB_TX]

Crescent wrench on the square drive shaft! One of those “can’t see the forest for the trees” type things. No problem someone here can’t solve.

[BB_TX]

If the cylinder came loose at the cylinder end (as opposed to the piston end), that cylinder that should have been stationary would instead have started moving. Likely that fitting caught on something and got pulled out. Your hose is probably still good. Maybe just a matter of a new fitting if you are lucky.

[ChuckS]

In your photo the Tee fitting is on the retract side of the cylinder ( black Lippert hose ) is retract side of system

The threads on that Tee fitting are stripped and the threads on the cylinder itself probably don’t look much better.

You could try and chase the threads on the cylinder but then you will have to deal with metal shavings getting into that cylinder .. if you don’t pull that cylinder off and flush it many many times you risk getting metal shaving’s through the entire hydraulic system.. to include the entire six point leveling cylinders as well..

If it were mine I would order a new cylinder and replace it and that tee fitting for then retract side and then bleed the system to get the air out

Use the existing cylinder PN tag to ensure getting the correct replacement cylinder .. if you can do all,of this at the location you are at then by all means order the new part and get a new Tee fitting for the retract lines

You will need at least 1 gallon of either ATF or AW32 fluid to replace what has been lost .. look at color of fluid if it’s red then ATF, if honey color its AW32

If the above work is not feasible at the location then use the Armstrong method shown in my video to get you home and then drop the coroplast or cut it (3 sides ) and replace the parts and then bleed system

** note.. when you remove the outer rod end off the slide measure the distance the old rod end is attached at . This will give you a “rough starting point” to install the new cylinder and rod ends.. then you will need to perform an open and close trst to determine if you need to adjust that outer rod end to habe the slide close and extend properly and seal properly

[scott802]

just wanted to say a huge thank you to everyone who helped today.
Will definitely need a new cylinder and tee fitting. Got the slide manually cranked in and the hydraulic line capped off so one slide basically works and we will drive the rest of the way home with one of the slides all the way in. Uncomfortable but it works.

Not sure how common a failure like this is especially on a 4 year old camper but i'm definitely wondering if I overlooked some kind of regular maintenance that would have prevented this from happening.
On the bright side, I sure learned a lot!
Thanks again

[Carl n Susan]

Glad to hear you got it sorta working for now. Be sure to take pics when you do the repair and let us know how it went.

[Mikendebbie]

Scott - sounds like you are handling the issue about as well as it can be handled. Those of us that are students looking to learn look forward to your de-brief, lessons learned and photos!

ChuckS - i appreciate you monitoring the forum and helping those in need!

[ChuckS]

Glad you were able to get the slide pulled in and cap off the retract line . Well done..

Regarding the retract Tee fitting that was yanked out of the cylinder body my speculation is this…

There was insufficient working radius loop on the retract line and that put undue strain on the tee fitting where it is screwed into the cylinder body on the retract side

Over a period of time the combination of too small of a hose radius and 2000 psi pressure took its toll on the aluminum tee threads

… purely speculation on my part.

[mlh]

Originally Posted by scott802

yeah we are travelling actually in VA 5 days from Texas (home). One cylinder of the two on one side is completely disconnected. I'm going underneath to confirm but I'm sure there is almost like a u-joint at the end of that cylinder and that is completely broken off.

What part of Virginia are you in. I’m in western Va. Roanoke Co. If you are local maybe I can help.
Lynwood

[RacerX]

Originally Posted by ChuckS

Since you have a hydraulic line failed NO hydraulic fluid can flow to move the hydraulic slides in for towing..

There IS A WAY.. and I have used this method to manually close a hydraulic slide with gear packs .. like yours will have...

Watch my video.. this is a slow process but when you have no other choice THIS WILL WORK....

** NOTE - you still NEED TO MANUALLY open the Hydac valve for JUST THE SLIDES.... to use this method

https://youtu.be/x1sKi2KWN0Q

Very informative video ChuckS Thank you for sharing it.

[Mark7]

Too late to help here, but if I would have had this issue I would have removed the lines from both cylinders and then manually shoved the slide in with brute force.

If I were able to, I would have tried to catch the oil that is for sure going to come out of the inside fittings of the cylinders.

Not sure how I would have secured the slide for travel... maybe plug the ports where the lines were removed, but that can be sorted out.

Still curious how or why the "end broke off" the cylinder, or were talking about that fitting?

[thibdaux4@yahoo.com]

Could you send this to me ? thibdaux4@yahoo.com
Thanks in advance.

[ChuckS]

Originally Posted by Mark7

Too late to help here, but if I would have had this issue I would have removed the lines from both cylinders and then manually shoved the slide in with brute force.

If I were able to, I would have tried to catch the oil that is for sure going to come out of the inside fittings of the cylinders.

Not sure how I would have secured the slide for travel... maybe plug the ports where the lines were removed, but that can be sorted out.

Still curious how or why the "end broke off" the cylinder, or were talking about that fitting?

While your idea would work to get to the JIC37 fittings on either end of the two hydraulic slide cylinders you would have to drop or cut the coroplast.

The slides are held retracted via hyd pressure so the OP has none.. The simple method of using some blocks of wood placed on the inside top edge of each slide WILL keep the slides retracted while towing... There are a few other methods one could use as well to keep the hyd slides retracted while towing but wood blocks, wood strips, even a few cans of unopened soup, etc placed on a towel and then on the top TPO membrane to each slide will keep them retracted...

I carry 3 precut pieces of 2x4 for each slide ( the length for each slide ) is different on my RV for the two main hyd slides and hyd BR slide..

[Carl n Susan]

Originally Posted by thibdaux4@yahoo.com

Could you send this to me ? thibdaux4@yahoo.com
Thanks in advance.

What do you want sent to you? The link to the video? It was posted above your Post but here it is:

https://youtu.be/x1sKi2KWN0Q


And Welcome to the MOC!!

[scott802]

Hey everyone,
Just a quick update. I posted another saga during this trip from Maine to Texas that happened the last couple days Arkansas into Texas.
Posted in the tires forum because it's not really related to the slide issue, but I seem to also have 2 bent axles that caused my almost-new G-rated tires to have really bad wear on the outside and inside edges.

On the slide, in order to keep it in and secured during the last leg after manually cranking it back in we secured it by wedging large screwdrivers more or less to keep it from moving back out. That seemed to work.

Will keep you all posted and HUGE thank you from both of us.