Hydraulic slideout cylinder test

[daveinaz]

Yesterday, our 2008 Montana developed the dreaded slideout creep. Was traveling from MN to SD and when I pulled over at a rest stop, I saw that the main slide had creeped out about 4” at the bottom. Put it back in and drove another 100 plus miles — then the main slide was out again and also the bedroom one about an inch. After talking to Lippert, it seems that the problem is that one of the pistons is leaking. He explained that since all four slides are basically in a common loop, that one piston leaking can cause all of them to creep out.

He said to disconnect the extend hose at the cylinder while having someone press the retract button and see if fluid leaked from the piston. He said he would send me the tech bulletin on doing this, which he did.

However, upon reading the tech bulletin, it said to simply disconnect the extend hose at the pump manifold, plug the manifold where the hose was, press the retract button, and see if fluid came out of the extend hose. That seems much easier than crawling under the RV, removing the coroplast, and disconnecting each hose at the cylinder.

I didn’t understand why he told me to do it one way and then sent a tech bulletin that showed doing it a different way so I called him back and asked for clarification. He said that, yes, you could test at the pump manifold but there was a greater chance of getting air in the system that way.

My thought was that purging the system of air (assuming you get some in it) is not that hard and would be easier than removing all that stuff underneath the fiver to get to each individual piston.

So, have any of you testing for bypass as per the Lippert instructions — at the manifold/pump instead of removing the hose at the piston itself? And if i disconnect the hose at the manifold, how airtight do I need to seal the manifold inlet where I disconnected the hose - just plug it with something or do I need to get a screw on cap?

I was going to call a mobile repair guy since we are on the road, but they probably isn’t any point since they can’t get parts in before we leave.

I’m thinking that my best bet is to figure out which piston is leaking (either by myself or a mobile tech) and then remove it and take it to a hydraulic shop and have them repair it. Of course, Lippert said that would just be a band-aid solution. And, now that I think of it, I may as well test at the manifold/pump since when I remove the defective piston that is going to introduce air into the syste anyway.

Thank for your help.

[jimcol]

Dave, I had the same problem 2 years ago on my 2006. When taking the 5'er out of storage I had some creep in the bedroom slide. Retracted fine and I went on my merry way. After operating the slide a couple of times to load the 5'er I got to my destination and noticed the same slide had crept out, less than two inches. Following advice from this forum I checked my fluid level, added maybe a couple of ounces and cycled the slides in and out maybe 5 times. Hasn't crept since. I suspect maybe air in the lines from a small leak, but having been good for two years I not going looking for it. Your results may vary but then my fix required minimum effort on my part, and that I like.
Jim

[daveinaz]

Originally Posted by jimcol

Dave, I had the same problem 2 years ago on my 2006. When taking the 5'er out of storage I had some creep in the bedroom slide. Retracted fine and I went on my merry way. After operating the slide a couple of times to load the 5'er I got to my destination and noticed the same slide had crept out, less than two inches. Following advice from this forum I checked my fluid level, added maybe a couple of ounces and cycled the slides in and out maybe 5 times. Hasn't crept since. I suspect maybe air in the lines from a small leak, but having been good for two years I not going looking for it. Your results may vary but then my fix required minimum effort on my part, and that I like.
Jim

Thank you. I will try pulling all the slides in and checking the fluid level first. Like you said, try the minimum effort easiest stuff first!