Front Jack stops

[top flight]

2007 HR Vacationer Diesel.  Lowered hydraulic levelling jacks, Front one first.  It started to raise the coach and then stopped, heard noise from it but would not raise any higher.  Both rear Jacks worked fine.  Checked reservoir in rear compartment and fluid was low, added correct fluid as per manufactures instructions, did not solve problem. Any ideas would be greatly appreciated. 

[CAT Stephen]

RP,

 

Do your leveling jacks have visible retraction springs? 

• If the jack does have visible retraction spring(s), then you will need to replace the existing jack retraction spring(s).
• If they do not have visible retraction spring(s), then the retraction springs are internal which means that you will need to replace that entire jack.
  • This will be $$$$.$$  (i.e. ~$1000< plus 1 -2 hour install labor)

[OhReally]

First: Check all electrical (battery) connections at the pump and reservoir.

Second: Run jacks (especially front) up and down several times.

Pump uses a fairly large current and loose connections can cause issues. If low fluid you may have introduced air into the Jacks and lines to the jacks. If so, it may behave like you describe. Running jacks up and down should get rid of the air and fix your issue.

Lastly: You shouldn't loose much, if any, hydraulic fluid under normal usage. Fix leaks in system if you have lost a fair amount.

[Martinvz]

Two additional things to do: (1)clean the shaft that extends on each jack with spray lithium grease or WD-40, either will work. 

(2) Check the jacks for a grease zerk fitting and, if available, grease the jacks that have such fittings. 
These may not solve the problem but will make them work better. 

[jacwjames]

Can you hear the pump running while you are trying to raise the front,  is the pump straining?

My front jack would not raise the front all the way.  It didn't have enough pressure.  I was doing some searches on line and found the attached document.  The pressure is adjustable via a relief valve.  From the document RVA set the pressure on the pumps the shipped but it would only lift 11,500 lbs, which in some cases is not enough.  

Not sure RVA corrected this as the document was dated Oct 1999.  It commented that they suggested that an owner should raise the front jack to where they will need it to be level  >>> but for me I ain't that good at leveling and still have to make final adjustments.  I'd rather have the ability to raise the front as needed. 

So I went ahead and adjust mine so there is enough pressure to lift the front.  I didn't have a pressure gauge so did multiple test so I had just enough pressure to fully extend the jack.   

As with all my comments "Proceed at your own risk"

_RVA Jacks - How To Increase Pressure.pdf

Edited December 18, 2023 by jacwjames

[bobdinsmore]

I think you have the RVA jacks. I fixed the same problem by opening only the front jack T-handle on the hydraulic pump SLIGHTLY, as mentioned by JimJ's reference to the RVA pamphlet. It's been operating flawlessly for years.

[top flight]

Thanks everyone, I will follow all advice and report back

[top flight]

Re springs, visible, no problems retracting so assume they are ok.  Re leak, checked all around while in storage and here at rv site, no visible leaks.  I will keep checking.  Thanks all for your time and advice