Hydraulic Leveler Repair and Bleeding

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Kurt63

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Sep 25, 2007
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Valley Springs, CA
One of our rear HWH jacks has a small leak and I was wanting to know once you change the hose do you need to bleed the lines?  If so, how?  Bleeding brakes and clutches you have a pedal to pump so I am not sure how this would be accomplished and I could not find much information.  I did find a post on the FMCA site that says the tank cap is vented and that is how you expel the air in the lines.

Anyone have experience with this and input would be appreciated. 

Thank you,
Kurt
 

Tom

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The systems are self-bleeding and, yes, the cap is a vent. Operate the jacks a few times, and keep an eye on the oil level.
Edit: Fixed typo.
 

John From Detroit

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Davison Michigan
Tom, I wonder about that,, On my Power gear jacks epically the rear ones show clear evidence of air in the line, They have been extended full length a few times but they still show clear evidence of air in the lines.. I think a bleed out may be needed.

Any suggestions on how to do it?,,, (I may, some day, replace the fitting where the hose goes in with a "T" fittting and add a brake bleeder valve,, That should do it)
 

Gary RV_Wizard

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I'm guessing it is a Power Gear jack system in a 92 Pace, but correct me if it is some other brand (the system may work differently).  Any air in the pressure lines should bleed back into the fluid reservoir when the jack is raised, and the reservoir is vented (unpressurized). Just run the jacks up and down a few times to get rid of air.

If you feel you must manually bleed it, loosen the line at the valve for each jack while the jack is at least partially down and under pressure. In the typical Power Gear system in which a spring returns the jack to the raised position, there is no pressure in the line when the jack is up. If the jack leg has no return spring, then it is hydraulically pumped in both directions and has pressure both ways.
 

Kurt63

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Sep 25, 2007
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Valley Springs, CA
There are springs.  I will fix the leak and try them several times.  The jack has a tendency not to lift all the way and makes the coach not sit level.  I have the procedure on how to adjust the leveling and will do that once the leak is repaired. 

Thanks,
Kurt
 

Gary RV_Wizard

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If the jack doesn't retract via the spring, clean the ram and wipe with ATF to lubricate. Some Power Gear rams have zerks to grease the seal on the shaft. It will be at the lower end of the ram tube.
 

Kurt63

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Sep 25, 2007
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Valley Springs, CA
Was underneath looking at the jack and it is indeed HWH.  I cleaned the grime off and set a piece of cardboard underneath to so if I can determine where it is leaking.   
 

Molaker

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Jun 16, 2010
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Springfield, Mo.
Kurt63 said:
Was underneath looking at the jack and it is indeed HWH.  I cleaned the grime off and set a piece of cardboard underneath to so if I can determine where it is leaking. 
Shortly after I bought my MH (used) I noticed the foot of the right front jack getting wet from ATF when left down under pressure.  I fought it for a while, refilling the reservoir occasionally (which is a big PITA).  Finally, I contacted HWH.  They did not have any rebuilt jacks of my vintage in stock and I would have to remove the jack and send it to them for rebuild.  I removed the jack and noted the leak appeared to not be a seal.  I found a tiny pinhole in the very top weld of the jack.  I cleaned the area well, pinged the hole with a center punch then soldered the hole with silver solder.  It has never leaked since.  However, I do believe the system has air in it now, probably from running low too many times.  My jacks are the folding type with a small actualling cylinder to swing them down.  Sometimes one of the rear jacks won't swing down without running that side long after the front jack touches down.  I suspect air in the actuating cylinder.  When physically able again (surgery coming up), I'll try bleeding it and see it it resolves the problem.  I'll report back once I get the job done.

My biggest challenge in bleeding the system is adding fliud.  The reservior is strapped to the frame with about 3" of clearance above the refill cap.  No way to see what you are doing.  A basting bulb is about the only way I can add fluid and then it's a guess...and a mess.  Maybe while I'm waiting to heal, I can conjure up some better way to do the job.
 

Just Lou

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Molaker said:
My biggest challenge in bleeding the system is adding fliud.  The reservior is strapped to the frame with about 3" of clearance above the refill cap.  No way to see what you are doing.  A basting bulb is about the only way I can add fluid and then it's a guess...and a mess.  Maybe while I'm waiting to heal, I can conjure up some better way to do the job.

Tom, maybe you can adopt/adapt the technique that I use in my one-man brake bleeding operation.

I use a siphon squeeze ball to fill the reservoir while I frantically run from cockpit (to apply the brakes) to the wheel being bled (to check the color and condition of the fluid filling the catch receptacle).
 

Molaker

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Just Lou said:
Tom, maybe you can adopt/adapt the technique that I use in my one-man brake bleeding operation.

I use a siphon squeeze ball to fill the reservoir while I frantically run from cockpit (to apply the brakes) to the wheel being bled (to check the color and condition of the fluid filling the catch receptacle).
I've tried that, at least, much like that.  The problem I have with that method is there is no way I can run anywhere.  Just crawling under and back out from under the MH is something akin to some kind of medieval torture.  Once down there, it's best to stay there until the job is done.
 
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