Level-Up hydraulic jacks - trouble retracting 1 of the jacks - cold weather

[steve&renee]

Had to take my rig in for recall work Dec 4 in Minnesota. Temps were below freezing (~28 F). Hooked up to my TV, then, as usual, hit "Retract All" on the Level-Up control panel. Rear and Front jacks were down, and all jacks started retracting -- except the front left jack.

The "Retract All" operation completed and notified me that all jacks were up. But the front left jack was still down. I switched to Manual mode and tried to retract the Left jack(s). Retracted a bit, then the solenoid clicked off. Powered the Level-up controller off and on, switched to Manual, and hit retract Left. Retracted a bit, then the solenoid clicked off. Repeated this sequence about 10 times and the jack finally retracted completely. Whew!

Got the rig to the dealer where I dropped it. All jacks extended just fine when I dropped the rig for service.

Service completed, and I picked up the rig today. Temp was around 26 degrees F. As I was hooking up, all jacks retracted except the front left. Tried the same trick of switching to Manual mode and retracting Left. That didn't work, but using a "power off/on/Manual/retract Front" sequence did. Again repeating this sequence, in each iteration, the jack retracted an inch or so, then the solenoid clicked off and retraction stopped. Repeating the sequence enough times resulted in a fully retracted jack. When I got the rig back to storage, all jacks extended just fine.

My batteries are Lithium, so I had discharged them to around 40% SOC for winter storage. That's what they were when I picked up the rig for service. I left the batteries connected and the solar active during the 1-day service visit. I was hoping the solar would recharge the batteries some during the service visit, but it was so cold the battery BMS's prevented the solar from charging -- so when I picked up the rig and tried to retract the jacks, the batteries were at 30% SOC. Even so, I don't think the problem retracting is battery related. My battery monitor is showing 12.8 V @ 30% SOC.

The LCI manual for Level-Up (https://lci-support-doc.s3.amazonaws...cd-0001531.pdf) shows a pressure switch and a retract valve block that controls both middle and front jacks. The middle jack seemed to operate just fine, so I don't think it makes sense to suspect either of those components. It's also odd that the front left jack extends normally. It's just a problem retracting.

BTW: plenty of hydraulic fluid.

I'm not making much sense of the wiring diagram in the LCI manual. It doesn't appear to me that there are separate solenoids for each jack - but in my case, the solenoid only trips off for the front left jack when I retract.

Any ideas?

-Steve

[howson]

Any ideas?

Excellent write-up, Steve.

First items I'd suspect are the jack or retract hose/circuit for that jack. On an aircraft we used to attach a "swap over" setup that would reveal if the problem was in the end component (problem did NOT follow after the swap) or in the controller (problem DID follow after the swap). Not sure that's applicable to an RV's hydraulic system, but if you could attach temporary extensions to where the return lines attach to the front jack (swap left and right return lines) it would help isolate the problem.

If you were able to swap the lines and the jack still didn't work right, it's the jack. If the lines are swapped and the other jack now shows the symptom, it's in the line or controller/valve.

[TedS]

You might try checking the trombetta solenoid. You could jumper a battery to it.

[Yoda]

At those temperatures any water in the hydraulic lines would freeze causing a restriction. Things would still work, but very slowly. The fact it works in reverse is not an issue as the fluid would move the ice away from the choke point. You could try bleeding the line at the cylinder fitting. I have had this happen on my tractor a few times. Condensation was the problem as I was somewhat low on hydraulic fluid. Once fill up and run a while it went away. There might be an additive to help in this situation, but be very careful is is compatible, A call to Lippert my also offer solutions. I believe they have a 24/7 help line from what I remember.

Just brainstorming here
Keith

[steve&renee]

howson TedS Yoda

Thanks for the suggestions, guys. I'll do some troubleshooting tomorrow and report findings.

-Steve

[steve&renee]

howson TedS Yoda

Follow up on hydraulic jack retracting trouble:

I brought the trailer home from storage this morning. Yesterday was warm (50 F), and it didn't freeze overnight. When I hooked up to bring the unit home, it was around 38 F. Same problem with the same jack. It would retract a little, then the solenoid would click off and retracting would stop. Repeated the afore-mentioned power off/on/retract sequence several times and I got the jack all the way up. Got home and the jacks behaved normally during unhooking. This was as before. The problem is only retracting the one jack (but I think it's a problem only when the jack is not under load -- i.e., not carrying the weight of the trailer).

Used Ted's guide and checked the solenoid. Solenoid is working fine.

I chickened out on Keith's idea to bleed the hydraulic line. Sounded too messy. Same with Howard's idea to swap hydraulic lines. That left swapping electrical, but I got confused trying to decide which wires to swap.

Turned out I didn't have to swap anything. It was warm all day -- about 45 F when I hooked up. All the jacks retracted just fine. No symptoms.

I'm thinking the problem is related to the cold. This is my first trailer with hydraulic jacks. When I picked the trailer up right after purchase, I was talking to a tech at the dealer about how great the hydraulic jacks were. He said something like, "Yeah. Until it gets cold. Then they're not so great."

I do have one hypothesis: The slide-out hydraulics have auto resetting breakers. When my problem manifested, the jack would stop retracting and become inoperable until I powered off and on again. Does anyone know if the hydraulic leveling jacks have re-settable breakers. Maybe when it's cold, the jacks pull more current and the breaker for the problem-jack just trips more easily than the other jacks. Maybe I should find the problem-jack's breaker and replace it?

-Steve

[Country Campers]

Steve

I do not think that you have one breaker for each jack. You will have one for the slides and one for the jacks , or maybe one for each set of jacks , you do have 3 sets of jacks right? So if one of the front jacks works properly then the breaker should not be the problem. What should happen is when you energize a switch to tell it to extend the front jacks this breaker should open a solenoid on the hydraulic pump to allow fluid to go to those 2 cylinders. On the same note when you use auto level the sequence should energize the breaker only to allow fluid to go to one cylinder at a time , boy this seemed much better in my pea sized brain until I started to type it out and now I think I typed myself into a corner. I am wondering now if there is an issue with the cold temps and the solenoid not going to the proper location to allow for both front jacks to be retracted. I sure hope there is someone here that has had one of these apart to let us know how they work.

I am guessing that none of this helps but maybe there is one little tidbit that will tweak a funny bone in a smarter person than me.

Brian

[steve&renee]

I do not think that you have one breaker for each jack. You will have one for the slides and one for the jacks , or maybe one for each set of jacks , you do have 3 sets of jacks right? So if one of the front jacks works properly then the breaker should not be the problem. What should happen is when you energize a switch to tell it to extend the front jacks this breaker should open a solenoid on the hydraulic pump to allow fluid to go to those 2 cylinders. ...

Brian

I do have three sets of jacks. FYI: when I retract or extend the front jacks, the right front extends first, then, when the right front makes ground contact, the left front extends. Only when both jacks have made ground-contact do they both extend in tandem. I was real learning curve for me to get used to that behavior. Retract works similarly. One jack at a time.

I do know that when people were experiencing the undersized 50 amp slide-out breaker problem, the symptom was that the slide-outs would begin to extend, then the breaker would trip due to excess current, then the breaker would auto-reset, then retract would resume. That's very similar behavior to what I was getting on my front left jack.

One of my problems is my wiring and hydraulic plumbing doesn't seem to match up with the online LCI Level Up manuals, so I'm having difficulty identifying the breaker(s) in my rig.

-Steve

[ThePowells]

Steve, I remember a similar discussion before and the recommendation then was draining some hydraulic from the reservoir and then adding a CAT branded hydraulic fluid to eliminate popping and sticking. Then the gentleman from Lippert did a presentation at the National Rally and changed the recommendation to use motorcycle fork oil.
Does any of this ring a bell with anybody else?

[howson]

Maybe when it's cold, the jacks pull more current and the breaker for the problem-jack just trips more easily than the other jacks.

Much more likely that the internal seal inside the jack is bypassing when it's cold, Steve. There's a test you can do, but as you say "it would be messy"--it's a Hydraulic Cylinder Test: https://lci-support-doc.s3.amazonaws...cd_0001910.pdf

[TedS]

Follow the heavy red wire connected to the trombetta solenoid. That should lead you to the breaker for the hydraulic pump motor. It should be an autoreset breaker. On my previous trailer with the hydraulic system, I replaced what was a 50 amp breaker with an 80 amp manual reset breaker. No more annoying break/reset cycles. Current draw was measured as high as 67 amps during system operation.
The hose(s) to that leg may be pinched causing higher pressure demand when colder oil is being pumped.

[TedS]

Here is a hydraulic circuit for 6 point leveling.

[howson]

Follow the heavy red wire connected to the trombetta solenoid. That should lead you to the breaker for the hydraulic pump motor. It should be an autoreset breaker. On my previous trailer with the hydraulic system, I replaced what was a 50 amp breaker with an 80 amp manual reset breaker. No more annoying break/reset cycles. Current draw was measured as high as 67 amps during system operation.
The hose(s) to that leg may be pinched causing higher pressure demand when colder oil is being pumped.

It's a solid theory, Ted. Especially if there's a 50A breaker in the coach.

[ThePowells]

Steve, I found the video I referenced.
https://www.youtube.com/watch?v=X-YgRXHb6yY The discussion on the breaker starts at about 29:00
The discussion about the fork oil comes a little later and was to address a popping noise in the cylinders.

[JBill9694]

As far as I know there is only one hydraulic pump on board and it provides oil to the slides and the jacks. There are other threads documenting why the jacks/slides move the way the do so I won't go into that other than say that other than the stopping and stopping of the one jack it sounds like the system is operating normally.

The 50-amp breaker for the pump motor can be a problem as TedS suggest (I've replaced mine twice). Once steve&renee locates the breaker it can be jumpered across to see if this solves the problem. If it doesn't then it may be time to move into the messier troubleshooting.