23 replies to this topic

[DirtyDog]

I'm helping MikeDahlager repost some info he had posted in a Yahoo group.

Hello, well it's done and it was one heck of a chore. Drained and flushed the whole system with air. And the top lifted for the first time in three years. Robert the hydraulic fluid is rated for all weather. That is the fluid that John Deere adds at the factory for all there equipment. East coast, West coast and all points in between. They use the same fluid. Ted I found out the hard way about filling the system when the top is up.*** I had a bit of a mess with my 8' non cab over. Learning experiences are always fun.

So this is what I did to drain and flush the system. First off I removed the fitting at the furthest cylinder from the pump, which is the right rear and attached a rubber hose to it. I placed a container below that. I pumped the pump until no more fluid was coming out. I then reattached the fitting temporally. Than I removed the fitting at the pump and placed a shop towel around it to catch any oil. Next I loosed and removed the fitting at the left front and used an air compressor to blow air thru the line. When that was done I reattached the fitting loosely and moved on to the next one. Right front, right rear and last the left rear. I then removed the pump from the camper and
turned it upside down to make sure there was none of the old fluid in the reservoir. With that done I reinstalled the pump, hooked up the main line and filled the system with hydraulic fluid. I had left all the fitting a little loose so as when I was adding fluid I was pumping the system to push any air out. When oil started to leak at all four fittings I stopped and tightened them all down. Topped off the reservoir and jacked up the top. As I said it is one heck of a chore, but well worth the effort. It's been a long day and I'm
bushed! Till next time, Harold


Note: In the '01 Op Manual they say--"Bleeding the system is done by running the
pump for 15 seconds in the down position with the gate valve in the
open (or lowering) position."

***Make sure that the top is in the lowered position before you fill up the reservoir! When I spoke to Brian at Alaskan he told me that it is not uncommon for folks to fill it up when the top is up, and then you can imagine what happens when the top is lowered!

[jrfromafar]

I may need to do more than bleed my system. I bled the system and it helped, but only getting a small umph from each pump, 105 to be exact to raise the top. O rings seem ok - nothing is leaking. Any ideas?

[Mike S.]

Sounds like the pump is bypassing probably needs new O rings,  I have the electric system so I don't know how you fix it but it should be straight forward.  One of the other people will know how to take your pump apart.  Every time I play with mine its messy though, haven't figured a way to empty 2 quarts of oil with out getting it all over everything.  Good luck.

[Rusty]

I'm getting ready to purge a system myself and plan on installing a valve at the pump for draining most of the system....taking the handle off the valve for "safety"....you have to think about doing this....Mine has been 46 years without a drain and change.

[wyocoyote]

I too am "having trouble getting it up" since having reinstalled my older (late 1980's) electric hydraulic pump by Oildyne in my Alaskan.

Unfortunately (or fortunately depending on how you cut it) I mis-diagnosed the issue. My switch and maybe some other electrical fried. I didn't figure this out until after removing my pump making a hell of a mess (I now know a rounded head chopstick makes the perfect plug for the lines if you are replacing the pump but not doing a complete bleed)

       Even more unfortunately I should have tested the pump motor with 12v before taking to my local electric motor repair shop. Comedy of errors to say the least, but it was disassembled before being tested passed through 3 different guys hands and by the end no one knew how to put it back together correctly. Caveat: There are very important spacers (washers) to keep track of when pulling the armature from the electric motor and key ball bearings below the "fingers" in the hydraulic pump section.  An important FYI the very same motor and pump with a different part number is Available through Parker. New PN should be Parker Oildyne HRS-519-000-BOR-S mini electric hydraulic pump. old number on mine was Oildyne Intertech model 910631037 If you just need the electric section, they are still used for outboard trim/tilt hydraulic motors and may be found more cheaply through companies like ARCO out of florida.

Okay just wanted to get that potentially valuable to someone needing to replace their electric pump or hydraulic section out there. Brian tells me what Alaskan has to offer now wont likely fit my camper and that these are/were excellent units.

     On to my dilemma: I have it all reinstalled. It is of tanatamount importance your pump is primed after removal and replacement. You got a bubble in on my pump there is a  the pump its not going to prime itself off the resevoir I found. Bleeding by running the pump with the lever in the down position hasn't seemed to work either much to my chagrin. Priming the pump is a pain, at least the way mine is plumbed because the place to prime the pump is on the bottom. You open it with an Allen wrench. I had to twist the connectors one direction (the L connector needed to face up in the same direction as the priming orifice. Ughh. I have gotten mine where it only gets a small umph much like jrfromafar above. It is still possible the hydraulic pump is at fault but it seems to shoot fluid pretty well now. I have found what may be a fill valve atop the manifold. I'll try and speak with Brian again soon at Alaskan, then post.

[wyocoyote]

After talking to Brian at Alaskan sounds like even my in older system air in the lines is very unlikely to be part of my issue. The system is indeed open and self purging. H tells me that even when they build a new one, the top goes up without having to fill the rams. I thought I was dealing with a closed system like hydraulic brakes initially.

He said check valves can be at fault (on those with check valves) and or the up/down valve itself. I'm removing my hydraulic pump again. Aaargh. sure seemed to be pumping well.

[Boise]

Got my camper in my shop for spring maintenance and purging the hydraulics.

1.) Problem is that I loosened the up/down valve maybe a little too much and now the pump is not pumping. Perhaps the check valve seal needs replace?

2.) Checking the fluid level I am 3 inches low?


Pardon the interruption, the up/down valve wasn't,t closed all the way--there was a little resistance that "fooled me". So the pump is fine, I may leave well enough alone. The ideal do of a drain valve to purge the system does sound appealing though.

Edited by Boise, 16 February 2017 - 09:06 PM.

[draker3838]

I had a revelation the other day with my hand pump that really helps with the softness on the downstroke. Figured I would share for others with the same problem.

 

As mentioned in other places, first and foremost, the fluid level must be topped off or else air will get sucked into the pump and the top won't be going anywhere. I had a bad O-ring on my pump which caused the thing to leak with every downstroke and I have a feeling Ill be cleaning it up for a while yet! After replacing the O-ring, I lifted the top without sufficient fluid so midway up, I added more fluid and the stroke was still very soft although I was able to get the top up after pumping 50+ more times. After dropping the top, I began pumping  and the result was pretty solid, but still a bit soft. I thought through the pumping mechanism and realized that the "cheater bar" hits the floor before the pump maxes out in the downward stroke. If there is air in the "pumping cylinder," It will remain there until the pump is completely maxed out to purge the air then draw in hydraulic oil on the upstroke. What I did to purge the air is put the lever in the position to lower the camper, then, without the cheater bar, give the pump a few strokes making sure to push it all of the way down and pull all of the way up again. Finally, I switched the knob to the raise position and began pumping. Immediately, the full stroke is solid all of the way to the top. 

 

I replaced all of the O-rings and seals on my pump twice and it resulted in no leaking but weak pumping action. I think having air in the cylinder was my problem and may help others with the same problem. We were looking at replacing the pump entirely, but now it works good as new. 

 

I hope this helps other Alaskan owners out there! Cheers!

[David Gendron]

Here is a question while talking about changing the hydraulic fluid!! Is any one that have switch the fluid to synthetic for winter use?

If so what grade/what brand!!

[PackRat]

I'm about to replace the whole ram on my LF corner as it has split...the camper came to me with two hose clamps around the end just above where the line is attached and the PO did get a complete ram/tube assembly from Brian prior to my purchase of it. I know about how to support the top while performing the change but I am anticipating  some loss of hydraulic fluid during that process.

 

I found out that the original fluid was "Mil Spec. H-5606-A" which is a mineral oil product and should not be mixed with a fluid like ATF or motor oil. So, in trying to find that I see that NAPA and O'Reilly's hydraulic fluids do not list that Mil Spec and are apparently NOT mineral oils.

 

A quick call to Alaskan gave me an answer...the lady suggested a "cold weather" hydraulic fluid for things like Caterpillar or Deere systems. The internet lists "H-5606-A" as used for things like landing gear on 1940s era aircraft...as it is a cold temperature adaptable fluid suitable for retractable landing gear.

 

What are you guys using and where did you get it? As it has to be OK for the O-rings we use and suitable for the pump/ram assemblies in the Alaskans, I suppose that is why a mineral oil is suggested and why we should not be mixing types.