Question for the hydraulic guys

[sandy43]

For you hydraulic guru's, I'm trying to solve a problem that's totally got me stumped. My Alpine has been sitting for about 10 weeks on concrete. The front dropped about 1 1/2 inches. I noticed this morning it wasn't quite level. I have the tank marked with slides and jacks in and up. also when slides and jacks out and down. Tank shows good either way. I've checked all hose connections and anywhere else were a leak could occur. Nothing, all appears good. My question: what would make the front jacks retreat 1 1/2" ?
I'm also going to post this on the Alpine forum.
I would really like to solve this problem. Any and all help is greatly appreciated. Thanks

[flybouy]

I'm no "guru" but you can have a fluid leak that isn't external. The hydraulic cylinder can leak pressure from one side of the piston to the other, or one of the valves could leak back into the fluid resivor. One other possibility is air in the system. Hydraulic fluid cannot compress but air can.

[gearhead]

Mine does too. I changed hydraulic fluid last fall and still does it. I don't think I'm at 1 1/2" though. I'm not showing any leaks either. I would agree with what flybuoy says.
Do you hear an occasional pop or creak from the trailer? I do.
I just hit the auto level again.

[Big 417]

You guys are suffering from the infamous jack popping. Common problem. There's lots of stuff on Google ��. The cure that works for most is to replace your fluid with 1 jug or 2 of "fork oil" or something like caterpillar antistiction fluid. It's a hydraulic additive.

I need to do mine this season. Pops every once in a while and wakes up the wife lol

[gearhead]

You guys are suffering from the infamous jack popping. Common problem. There's lots of stuff on Google ��. The cure that works for most is to replace your fluid with 1 jug or 2 of "fork oil" or something like caterpillar antistiction fluid. It's a hydraulic additive.

I need to do mine this season. Pops every once in a while and wakes up the wife lol

I added a quart of Torco motorcycle fork oil when I replaced my oil. Might should have added 2 quarts. I used Valvoline synthetic transmission fluid as a hydraulic fluid. My popping isn't bad enough to do anymore about it.

[xrated]

flybouy is most likely right on the head of the nail with his comments. Internal leakage that gets past a seal or piston and "vents" to the tank is not going to be seen externally....no visible signs. On a lot of these trailer systems, the is a common line for pressure to each cylinder and if one is leaking past and going back to the tank, since the lines are common to each other, both legs will move the same amount.

[travelin texans]

Fluid temperatures also affect the popping/creaking & the level fluctuations.
LCI recommends exercising the jacks monthly if stored for extended periods, wipe & spray with silicone spray each time they are retracted.

[Big 417]

I've heard some units need the set screw on the valve tightened down. Apperently some slip past the scrupulous quality control folks

[LewisB]

Add me to the list; over several weeks, my 6 point LCI Level-Up system will slowly drop the front rams. Not much, no "pops" or creaking, just barely noticeable. As already suggested, I put the Morryde steps up, then just auto-level again. No external leakage visible, so I just assume it is the front jacks valve leaking by very slowly. I have checked the valves (when I tested the manual emergency process) but have not tried a fluid change or additives.

[larryflew]

Flybouy is right on. My Alpine has 5 new lefts out of 6 due to leak through. If you go to anyone go direct to customer service at Lippert for the way to test them.

Lippert didn't actually do anything other than suggestions for a year but finally send tech to where we where. He replaced fronts in Arizona (2nd time so new ones done by dealer in MN leaked through also) and 2 sides. This was February. Another of the same fronts going down problem in summer and they send a guy to replace in Minnesota.

Just to be clear ours is an add on system so we have 2 pumps and 2 tanks. Slide hydraulics and lift hydraulics are separate.