hydro pump spins but nothing works

[Norm Vernon]

Having issues with the hydro pump for the jacks and slides on a 2004 Marquis. When trying to use any function the motor spins and the rpms grow till its spinning many times the rate it should even if it was unloaded. Does anyone have a magic solution or place to check ? The local rv place determined the shaft from motor to pump is not broken but wasn't able to go any farther due to the size of the project so reinstalled in the coach. So seems to be either a valve or the pump itself. Does anyone know of a replacement pump or complete set up available ?

[Frank Bergamo]

Did you check the fluid reservoir?

[Norm Vernon]

yes

[Fred Brooks]

    Norm,
Is your leveling system an HWH computorized air and hydraulic? Please identify, Fred

[Norm Vernon]

yes - the metering block has a RVA tag on it - some numbers are missing but the power pack seems to be a 45something JII which I am sure is obsolete. I was able to verify power at the valves for the slides when pushing the in/out buttons so I am back to thinking the pump has self destructed and now the motor just spins away with no load making no pressure. RVA is in Washington close to where we plan to be in 2 weeks so as I am in Canada it will be faster to just pick up a new power pack directly from them as we drive by and fix it at our destination. At least that is my plan at the moment till Monday when I can talk to someone at RVA to confirm there is a retrofit power pack and that they have one.

[Eric Maclean]

In the coach assist section there are some of the manuals for the RVA systems but they don't cover the slide controls however they work much the same perhaps you can gleen enough information to tackle the repair .
If you have no pressure build up at all I would focus my search on the pressure relief valve problem .
( Possibly stuck or a broken spring)

Below are links to the last known RVA parts

The 45 in your part number likely refers to lift rating RVA had 4 lift rating models a 16 a 22.5 a 35 and a 45
The following web site has some of the parts for the RVA systems.

Hope this helps
Eric



https://www.rvajack.com/


https://www.rvajack.com/RVA-Hydraulic-Pump-Assemblies-and-RVA-Hydraulic-Pump-Parts

[Fred Brooks]

      Norm,
  I agree with Eric concerning the pressure relief valve. The quick way to prove that TEMPORARILY would be to remove the pressure relief valve and install a pipe plug. Briefly turn the system on and then off. If you get pressure, you have proven that is the issue. If not, work your way back towards the pump. Hope this helps, Fred

[Eric Maclean]

Norm
In the coach assist there is an RVA memo on how to adjust the pressure relief valve it has a cross sectional view of the valve.
I'm not sure that simply removing the relief valve and plugging the hole would work as I think it would just allow the pressure to by pass .
But if you remove the pressure relief you will have a direct port to the pump if you run the pump with the pressure relief valve out it should pump fluid right out the whole creating a mess but proving the pump is working just thread in a hose nipple into the hole and place a hose on it into a catch bottle to see if the pump is moving any fluid when the motor runs.
When you have the relief valve out you should be able to dismantle it to check the spring and relief valve itself.

Hope this helps
Eric

[Norm Vernon]

So the update and final result - one of the gears in the pump had broke into 6 pieces so the motor would spin but not pump fluid. RVA was very helpful both with a replacement updated power pack and how to hook it up. Oily job but now back in action. Thanks for the help along the way.