Hydraulics not working, top won't raise

[lyn6wist7]

2003 Hi-Lo Can't get top to go up. Jacked it up high enough to get to the pump.
Had to put 1 quart of fluid in, but cannot find any leaks. Is there some way to bleed the system. Followed directions in manual using the manual lowering knob, did not work. Nobody around here works on these campers. When you press on the toggle to raise and lower it sounds like it is running but nothing happens. Anyone have any ideas on what to do? Thankx, Lynne

 

[JackandJanet]

Hello, Lynne, welcome to the forum and sorry you're having trouble. I need you to answer some questions:

When you say you "jacked it up", does this mean you raised the top using the manual lifting mechanism installed at the pump, or, did you place actual jacks under the top and lift it that way? This is an important question because it will tell me if you have a leak in the system.

Have you tried raising the top with the manual lowering knob turned to the extreme setting in BOTH directions? I'm trying to verify that that knob is not possibly open when you are trying to lift the top.

You say, "It sounds like it is running...". So you are hearing the lifting motor actually turning over, not just a "click"?

From your post, it sounds like you MAY have a defective seal in the system that is keeping it from holding pressure. This would allow any fluid that the pump is sending to the lifting cylinder to drain back into the tank. I've never heard of anyone having to "bleed" the system, it's not like a car's brake system, so I don't think that's your problem. But, if you could lift the top using the optional, built-in manual lifting device, you WOULD NOT have a leak and, the lowering valve would have been closed. This would imply, if the motor is running, that it is NOT turning the hydraulic pump.

There's a pressure release valve that is opened once the top reaches the full up position to prevent over-pressurization. If this were stuck open, it would keep you from raising the top, but, I don't think you'd be able to manually lift it either, using the built-in manual lift pump. I don't know where this valve is, or how it is actuated. But, when it opens, the pump motor makes a higher pitched sound.

In any case, I think a shop that deals in hydraulic system repairs could help you with this.

- Jack

 

[lyn6wist7]

Hydraulics not working

Thank you for answering my post,
The manual lifting mechanism does not work. We jacked the top up about 8" with 4 jacks so we could get to the pump. WE tried using the manual lowering knob in both settings, did not work.
You can hear the motor running not clicking.
Is the defective seal in the system in the pump itself or somewhere else?
I guess we will have to find a hydraulic fixing place. So far we haven't been able to find one in our vicinity. Or else put the camper up for sale to someone who wants a project. Thank you for your reply, Lynne

 

[JackandJanet]

Lynne - Your problem MAY have a fairly simple resolution. It's possible the manual lowering valve is stuck open, possibly with a bit of dirt in it or something. There is a way to clean it and that process is given in the .pdf you find in this thread: https://www.hilotrailerforum.com/f61/how-to-fix-top-half-creep-in-your-hilo-trailer-129/

But, if that's not the problem, then you likely have a bad seal in the system, or, the pump motor has somehow become disengaged from the pump itself. Any hydraulic repair place can surely fix either of these issues. Do a Google search to see if there are any such places nearby. Others have had seals replaced and it was not TOO expensive. I would think a faulty seal would be in the pump area, and it would probably be best if you could remove the pump from the trailer if it needs repair.

- Jack

 

[markpasqua]

I just ran into that problem on my ‘02 3302s. Check to see if when the pump is running you’re getting a lot of volume coming from the return line back to pump reservoir. If so, you have a bad seal in the cylinder, like I had. Pretty good job taking off the cylinder took about 3 hours. Had a hydraulic rebuild place rebuild the cylinder cost $180 but fixed it.

 

[JackandJanet]

Lynne, I don't want to confuse you so I'm going to try to clarify my earlier remarks in light of what mark just posted. He found that the seals were bad in the CYLINDER, that is under the trailer and that moves the ram along the guide rod to actually pull the lifting cables that raise the top. That is NOT the "pump" as I posted just before mark's post.

I suspect, from what others have posted, that leaking seals are more likely in the cylinder than in the pump. So, if you see the fluid rushing back into the reservoir, then the cylinder needs rebuilding. If fluid is not doing that, then the pump is probably not pressurizing the system and it is at fault.

I think I've got this right, but I've never had this problem, so if anyone else has better advice, please give it!

- Jack

 

[BigL-HILO]

The cylinder is located under the trailer. There is a plastic line running from the cylinder to the fluid reservoir for the air to escape when cylinder ram is extending. If you have fluid in the plastic line, you have a blown seal in the cylinder. If that is the case, you would need to pull the cylinder off and take it to a hydraulic or tractor shop to get it rebuilt. Treeclimber has an article - How to remove and replace the hydraulic lift cylinder - that is very helpful on pulling the cylinder off. I had to get mine repacked last year and it cost me $170.

 

[Usagi5678]

Confered with dear husband.

Do you have a fully charged battery? Is your function switch in the right position for lifting? You could possibly have air in hydrolic lines since you had to add fluid. It won't work properly until you get the air out. Hope this helps. Keep us posted.

 

[Agimsurvival]

Does anyone know what types of seals are needed for the hydraulic cylinder? I have a 1987 funlite with a leaking cylinder. I have a friend who works on hydraulics and has tools to fix it. All he need is a seal kit to to the job.

 

[Lvnv]

The comments about looking at the clear (mostly anyway) plastic return hose from the hydraulic cylinder are right on the money for troubleshooting.

I had the same problem a few months ago and the fluid was obviously going back to the reservoir via that plastic hose. Normally, the fluid returns to the reservoir via the same metal tubing that carries the pressurized fluid to the cylinder to lift the top.

Bleeding the system is not necessary, at least it wasn't on my 2004-05 17 footer. Bleeding takes place 'automatically' when the top is raised, popping sounds issuing from the cylinder as the air escapes from the cylinder to the reservoir via the plastic hose.

Removal of the cylinder is not trivial, but I was able to do it and I'm only an amateur mechanic. A local shop charged a bit more than $200 to rebuild the cylinder, and re-installing it was a bit easier after experiencing the extraction.

Adjusting the lifting cables so the top goes up evenly is not hard, but I wish I knew what tolerance there can be for a little bit out of 'even'.

I live in Central Florida, if you are nearby and want to talk.