I have a 1976 Hi Lo with no visible stickers on pump or cylinder. When I got it was all apart and down for fifteen years I have read most posts and fixed and lubed accordingly. Everything works and it just starts to lift but it doesn't. How do we know when a pump is failed pressure. Next, I am going bleed the system[turn on with the cylinder end off]. Any Ideas please.

The return line is also the high pressure feed line. The weight of the top forces the fluid back down into the resevoir.

Dumb question but is the resevoir full of fluid?

First you need to check the Pressure the pump is putting out. Connect a 3000 psi gage to the output of the pump. Pressure should be 1500 psi Max. If not try adjusting the pressure at the pump. The pressure relief valve could be stuck open or the lowering valve on the pump could be could be stuck open. There is also a manual lowering valve on the pump that must be closed and seating properly for the top to raise. If you do have the correct pressure at the pump then fluid must be bypassing the piston in the Hydraulic cylinder and the cylinder needs to be rebuilt. If you do not have a owners manual you need to download one here at the forum. Look at the diagram of the pump so you can locate these valves on the pump. If you need more info email me at loghm@aol.com and we can exchange ph#. Much easier to talk on ph than type. If you do email me put HILO in the subject blank.

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Jim L & Faye
2805C
2003 Silvarado diesel crew cab
2017 Silvarado, crew cab 1500 6.2L gas w/ 8 speed tranny
central VA

Thanks, give me a couple days, Cant play all week. I think maybe the manual valve might be open by the way it is acting.

before you try to even lift up the unit you need to lubricate and clean the cables , for the unit sitting that long , it is dryed out and ?? and also grease the hydraulic shaft real good.

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Paul Schoenfelder
Fort Pierre,South Dakota

And, don't forget to clean and lube the guide rod that runs parallel with the hydraulic shaft. Any good quality grease will work.

__________________
My Great Wife Joyce
2018 Jayco Jay Flight 21QB
Formerly owned 1705T and 2310H
2012 F150 4X4 SuperCrew EcoBoost w/Leer Cap
Reese WD Strait-Line Hitch
Amateur Radio K3EXU

The Switch works only one way, maybe its down? Does the cylinder squeal when all the way in/down? I tried the valve it was just cracked so I closed it righty tight no difference. Does the pump run when coming down or is there no sound because of the weight rushing fluid back to the pump? It has to run back and forth? Tomorrow, I will try a new switch and solenoid.

On my towlite, the pump doesn't run when lowering the top. The valve opens and alows the fluid back in the resevoir only. There is a chance your older trailer works differently but I doubt it.

The pump only runs when you are raising the top. When the top is fully up the pressure relief valve will squeal. You said before that the top would start to raise and then stop. You did not say if the pump kept running when the top stopped raising. If the pump keeps running and you hear the squeal when it stops then the pressure relief valve has opened and you need to adjust the pressure. If the pump is still running when it stops lifting then no need to replace the switch or solenoid. When you press the switch to lower the top you apply power to the lowering valve and the weight of the top returns the fluid to the pump. If the lowering valve is not closing fully then this could be your problem.

__________________
Jim L & Faye
2805C
2003 Silvarado diesel crew cab
2017 Silvarado, crew cab 1500 6.2L gas w/ 8 speed tranny
central VA

How do you post a new topic? My Daughter is good with computers and couldn't figure this out. Check out the web site RV.Net It contains an article about the family that left their HiLo for a consignment sale and now the RV is missing. We took our HiLO to our dealer for inspectiion. All was okay. The biggest chalenge was the 8degree weather and the brake controller not lighting up..Hubby walked home 30minutes to get the contact spray. Then we discovered the brake away switch had pulled out.Original to the trailer. Cost $12.00-new spiral red breakaway cable with a good size clip on the end. The end of a frustrating problem. Our HiLo dealer in Lockport,NY has five HiLo towlites for sale they apear to be new. Mantelli trailer sales,Chuck Carlson @716-625-8877. Chuck says they are listed on Craigs list.

Thanks jim I think a rebuild is coming.

Sam,
If you want to start a new thread go to the main page "Hi-Lo camper travel trailer forum", then pick a category that matches the subject that you want to post in. At the top left you should see the "new thread" button. Click on that and you will have a blank form window there to place your thread.

Rich

__________________
My Great Wife Joyce
2018 Jayco Jay Flight 21QB
Formerly owned 1705T and 2310H
2012 F150 4X4 SuperCrew EcoBoost w/Leer Cap
Reese WD Strait-Line Hitch
Amateur Radio K3EXU