raising an old hi lo

Inherited a 21 ft hi lo and am having trouble getting it to raise. Good battery, full reservoir , doesn't seem to be any binding. goes up about an inch and motor bogs down. I can lift with jacks but worried to lift too much. slide seems to be greased plenty and cylinder works. Was wondering if some air in the lines might be the problem and how to bleed it off? I think it is an 1983 model.

How do you know the battery is "good"? Try using Jumper cables with vehicle running to see if you get any more "oomph" . Or- check your battery with a multi meter- you should be getting 12.6 or better for a fully charged battery. IF that doesn't seem to be it- start looking to make sure nothing is binding like a bad cable or pulley. Id start with those two.

Rick

Yes just purchased a new battery 880 cca along with 100 amp jump from my charger. I have looked and felt for any obstructions but can't see or feel any. It still just starts up ( about an inch) then motor bogs down.

If it has the manual feature you should be able t raise it that way. It's slow going but that should tell you if you ate dealing with a hydraulic issue or an electrical/ motor one. There should be a place to put a " handle" into a sleeve right in front of the pump if you do have it. Like jacking up a hydraulic bottle jack.

There is a small lever at the pump, about the size of a short pencil.I will check if there is a hole around it to insert a handle. A short pipe type handle is in the door, 12" or so by 3/4". Thanks for all the guidance, I'm scratching my head.

Welcome to the forum

Smoodyr, Our forum members will keep answering you until you get your problem solved. Welcome from Niagara Falls,NY.

smoodyr said:

There is a small lever at the pump, about the size of a short pencil.I will check if there is a hole around it to insert a handle. A short pipe type handle is in the door, 12" or so by 3/4". Thanks for all the guidance, I'm scratching my head.

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That small lever is NOT a pump handle. It is the manual lowering valve. If the electric lowering valve should fail you can lower the top with the manual valve. The valve handle only moves a short distance to open or close the valve. If I remember correctly it moves left and right and if it has not been activated in a long time it may be stuck and will need a bit of pressure to get it to move. I don't have time to explain the pump system right now but will get back on late this afternoon with more info. The manual lowering valve must be fully closed to raise the top.

smoodyr said:

There is a small lever at the pump, about the size of a short pencil.I will check if there is a hole around it to insert a handle. A short pipe type handle is in the door, 12" or so by 3/4". Thanks for all the guidance, I'm scratching my head.

Click to expand...

If it has a manual pump there will be a part that looks obviously like the pump part of a bottle jack. By only moving an inch it makes me think there is something jammed between the upper and lower sections, or there is a problem with the hydraulic cylinder or the cable system. A good visual inspection should be done.

As RichR said something could be jammed between the top and bottom. Make sure a pulley has not broken and a cable has jammed between the pulley and the bracket. Now to the pump and hydraulic (hyd) cylinder. The pump provides the pressure and when the hyd ram reaches its full travel to lift the top the pressure in the system increases and opens the pressure relief (bypass valve) in the pump and circulates the hyd fluid within the pump so you do not overpressure the system. There is a adjustment on the pump to set the pressure that the bypass valve opens. You have to hook a pressure gage into the system to set this pressure. The psi that you set to is in the owners manual or the pump specs. I have it somewhere and can look it up. If the psi has been set too low, or the spring has lost its tension, or some trash is stuck under the valve seat then the pump may not be building enough pressure (psi) to lift the top. The same thing would happen if the electric lowering valve has gone bad or trash is stuck under its valve seat, no or low pressure in the system. Of course the pump could be worn out and cannot provide enough pressure. Next the hyd lift cylinder, if the seals are worn out it will bypass the fluid to the low pressure side of the piston and that fluid will flow back to the pump resevoir thru the transparant plastic tube that is connected from the ram and runs back to the pump resevoir. there should be NO fluid flowing in this tube when the pump is running. This should give you some idea how the system works. If you would like to talk on the phone on how best to approch this, let me know here and we can exchange ph#s and talk. These pumps are very realiable and my bet is it is something simple and repairable.

Thanks, as soon as it quits raining I will go look at hydro system for what
has been mentioned. my # is 620 251 9346 Thanks Jim L

I looked and do not find a low pressure line anywhere. I'm not sure if I am putting fluid in the correct place. I found one line running to cyl. and it seems to try to lift but only an inch or so. All cables seem to be free along with pulleys. Don't see or feel any blockage. The cyl. does have a small leak under load around ram seal but only under pressure. Put auto trans fluid in res.---Plastic cap with a screen filter sticking up ---like a breather vent for air escape??

Smoodyr, the plastic tank is the place where you add fluid. It should be between 1 to 1/2" from the top of the tank with the trailer top down.

To any of you that have had this problem: If there is distortion or roughness in the guide rod, could this cause the system to bind like he's describing?

- Jack

Thanks Jack I think I filled it too much and when I tried raising it just pushed the fluid out of the place I put it. It is pretty tight where the pump is located but I can see fairly well,just have to use a funnel with tube to fill. I'm thinking it is something I'm doing wrong. Last time it was up was about 3 years ago and everything worked well.

Im glad others have gotten involved in this post. But here are a few more suggestions:

There are three or four "doors" that could be open or lose that the top could be binding on while trying to go back up. If it were me- I would try to find something long, rigid, and skinny to slide up between the top and bottom and try to ascertain if there is indeed anything hampering movement. That said- this IS beginning to sound like a ram/pump-problem especially if it has been sitting for too long. Maybe seals have begun to try out, i.e "does have a small leak under load around ram seal but only under pressure." When trying to raise it it is certainly under pressure- I dont know- but maybe that "small leak" is significant enough to cause issues. By the way- how did you get the battery/pump compartment door open enough to get a new battery in there?? At some point it may be you have no choice but to start jacking up and reinforcing the corners (as you jack) to get up far enough to get a better look at the pump motor- etc . You also may want to call J&R at some point- and ask what their guess is based on the symptoms. ONE LAST THOUGHT: I guess for everybody- is there anyway the safety bar could be positioned to be causing an issue raising???

rick

Thanks for all the help, IT IS UP, multiple culprits.....Curtain rod, battery terminals not making solid contact, still had to jump with battery charger but is up. Now to evaluate what needs to be fixed. Thank you all again and hope to be camping next spring. smoodyr

Cool! Congrats! Glad you can get to things now.

- Jack

Great! Glad to hear it!