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papp · 09-29-2014, 03:08 PM

HI everyone . I have problem with my straight acting hwh jack not retracting like many of you. One of them has to be pry up with a 2x4. I call my locale hydraulic shop and they will repair for about $200.00. I am a mechanic by trade and I am sure with a bit of help from you guys we could come up with a procedure to do the repair our self.I have found a bit of information on other forum. Apparently there is a guide bushing in there that swell or corrosion gets between this bushing and the seal and prevent the rod from retracting, conteracting the force of the spring.Assuming that this is the problem, it has to be fix. It seem that this piston is not serviceable as per HWH.Apparently to take it apart you have to cut open the top of the cylinder and push the rod back through the top , removed the seals and clean the bushing till the rod slide freely and reweld the cap back on. I would appreciated your input. My rig is a 1999

Ray,IN · 09-29-2014, 03:52 PM

What is the HWH model # of your system?

papp · 09-29-2014, 04:13 PM

It is a 200 series lever control
Front jack is AP1611 SN 13557

GaryKD · 09-29-2014, 05:04 PM

Hi papp,
This is one of those jobs one might reconsider the DIY. For me, it is like changing the oil in one's car. I always did it myself. Then I found the price Jiffy Lube would do it for. The retail parts cost to me it about $12 less than the Jiffy Lube total cost. I no longer change the oil in my car.

The $200 price for a professional shop to rebuild the jack is a good price if you take into consideration the time it will take you vs. the shop to do the job.

For me, I kept 2 jacks when I had them replaced. I send them to HWH and had them rebuilt. I am ready for when the next time a jack decides to give up the ghost. However, you know the old saying, if you have a spare you'' never need it.

Ray,IN · 09-29-2014, 05:14 PM

To re-weld the top to the cylinder will cost at least $100. This is not a backyard welding job because their work must withstand the internal pressure, without leaking, and the cylinder must not be heated to the point of affecting performance or safety.

papp · 09-29-2014, 05:22 PM

Gary
I understand exactly what your saying and your are right about $200.00 is fairly cheap for a professional job. But being an industrial mechanic and work in a paper mill all my life fixing things ,I have this urge to take something apart and I also like to do it the right way. Like the old saying "A good mechanic always use the book"

regards
Norm

papp · 09-29-2014, 05:52 PM

In my case welding is not a problem. I'am just looking for somebody's input regarding a procdcure. I'am sure somebody had these jacks apart.

papp · 09-29-2014, 06:51 PM

Here what I have found on a UK forum

Hi. If it's of any interest, we have refurbished a number of HWH straight-action jacks. You are correct about these units being manufactured as non-serviceable, as I'm sure that HWH would prefer that any faulty jack was simply replaced by a new (and very expensive!) unit. Each sticking or slow jack that we have dismantled, has had the exact same problem, which I will explain: at the lower end of the outer leg casing, there is a plastic bush that is there to "squeegee" any dirt off the inner ram as it retracts. From new, these bushes were an "interference fit", in other words, they touch the ram, but don't cause enough friction to slow or stop the ram. Beyond these bushes, and further up the inside of the outer leg casing, there are two types of seal that DO work against the ram. A flexible "O" ring seal, and a solid seal. These seals are not, and in our experience, have never been the problem. The problem arises when corrosion occurs between the inner part of the leg casing (at the bottom, where it is open to the elements), and the plastic bush that was referred to earlier. What happens is that corrosion starts to build and swell the surface metal in the leg, between the leg tube and the plastic bush, which in turn forces the plastic bush to grip the ram around its circumference, and either slows the ram, or stops the ram from retracting. Obviously, more powerful springs can counteract this process as it gets progressively worse over time, but the real answer is to deal with the jacks by either repairing them, replacing them, or using levers to push them back up!! Obviously, none of these jacks have problems being lowered, as hydraulic force is going to counteract any resistance in the bush, and those folks with jacking systems that drive the legs up and down (on some Gulfstreams) will be feeling very smug! When we have stripped HWH jacks in the past, there are a number of cautionary measures that MUST be taken. The top cap of the leg has to be cut off ONLY when the ram is fully extended and emptied of hydraulic fluid (if a jack is really stiff, you may have to extend the ram by using compressed air). Prior to cutting the cap, you will need to remove the jack switch which sits on the top of the leg. Then, after cutting, be careful not to damage the proximity magnet that is set into the top of the ram in an alloy carrier, which is there to operate the switch that signals when the ram is stowed or down. There are also two bronze "half moon" shaped collets fitted around the top of the ram, that prevent the ram from blowing out the bottom of the leg. Once the cap has been cut off at the top of the leg, you will need to clean up the lower end of the ram (where a rounded end section and jack plate locating nipple have been welded), as it HAS to pass back up and out of the leg casing before any remedial work can commence. Once you have done this and not lost the collects, or ignored which way round the collects came out, then you should pick out both seals to avoid damaging them during the next stage. Once you have the seals out, you can "hone" out the plastic bush with varying textures of glass paper. You should keep testing your work by sliding the ram back in temporarily, using only silicone grease on the plastic bush, to check if the ram slides smoothly. Once you are satisfied that the ram operates smoothly in the bush, replace the seals in the correct order, fit the ram back in, replace the collets in the correct way, replace the magnet holder in the top of the ram (making sure that any metal filings from the cutting process are removed) , then weld the cap back on the top of the leg tube. Now comes the tricky bit...making sure that the welding has left no blow holes that could allow hydraulic fluid to escape under pressure. This can be a laborious process of fitting the jack(s) to the vehicle and testing the jack system under full load. If it leaks, take it off and re-weld the faulty area, if it doesn't leak--bingo! To repair a single jack is a painstaking and time consuming process, which is probably why no one is very keen to do it, favoring a simple replacement process, but at considerably more cost. I hope this is of help to anyone who fancies a go? Regards, Glenn. Just RV's. Lincoln.

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Here's what I have found on a UK forum

hogdriver · 09-30-2014, 10:15 AM

I think I'd call around to nearby RV dealers and see if any of the service centers has any discarded jacks similar to yours they'd give away or sell cheap for "exploratory surgery" before you cut into yours.

papp · 09-30-2014, 05:33 PM

I took my jack to the shop today .They comform that it is corrosion. And yes it has to be cut and push the rod up through and clean the guide bushing.It is better to cut the top with a lathe which I have access to, or you could use a mine grinder. I will attempt to do tne next one if I have too. Yes it would be nice to practice with and old jack.

Pigman1 · 06-14-2021, 08:15 PM

A couple of years ago I had a rear HWH jack that would not retract fully without a bit of help when it was at the almost fully retracted position. I took it to Red Bay and they replaced the jack for around $600 if I remember correctly. I took the "bad" cylinder home and had a local hydraulic shop repair it. My shop was ESECO, the Eastern Shore Equipment Company in Camden, DE which repairs all type hydraulic equipment. They got the necessary parts from HWH and repaired my cylinder for about $180. Only problem was that getting the necessary seals and parts from HWH took them 3+ weeks. THERE WAS NO WELDING OR CUTTING OF THE CYLINDER NECESSARY. These guys have been repairing cylinders, hoses, fittings and other hydraulic "stuff" for our farm equipment for a number of years. If these folks could do it, any competent hydraulic shop should be able to do the job. Even though I am a expert mechanic, I would not attempt this job. Just not my skill area.

Soppy · 06-15-2021, 08:12 PM

When I repaired mine , I did not have to cut the cylinder. There is a wire clip min the bottom of the jack that has to be removed. I used compressed air to force out the seals and plastic bushing. I sanded the bushing down on the outside then reassembled the jack. After a few tries, I got the piston to move freely. After a couple of yrs the jacks still move up easily with no leaks. It cost nothing for parts and took about half a day per jack. The hardest part is getting the wire clip out.

azpete · 06-23-2021, 02:44 PM

you can buy a hwh RAP0498 reman jack for around 400.00 inc tax and shipping.
all reman parts carry a one year warranty. or you can send it in to be rebuilt for much less. yes it does take time, but if you need it right now, try finding a reman cylinder. replacement part number is RAP0498.
i work full time for hwh corp

i do not solicit part sales or service work on this forum
paul maddox

AndyG · 01-03-2023, 07:02 PM

Quote:

Originally Posted by Soppy

When I repaired mine , I did not have to cut the cylinder. There is a wire clip min the bottom of the jack that has to be removed. I used compressed air to force out the seals and plastic bushing. I sanded the bushing down on the outside then reassembled the jack. After a few tries, I got the piston to move freely. After a couple of yrs the jacks still move up easily with no leaks. It cost nothing for parts and took about half a day per jack. The hardest part is getting the wire clip out.

Is this clip external at the bottom of the cylinder? Or, is it internal? My hydralic connection is near the bottom of the cylinder. When I remove the hyd fitting I can see a clip in the hole. If this is it how do I remove it. I'm very interested in getting the bushing out without cutting the cylinder apart.