Hydraulic cylinder protection...is it needed?

Well gang,
Been spraying down my HWH cylinders/rams with WD-40 for years, (about 6.5 years to be exact) and wiping them off but not totally, leaving a tad film on them. And guess what, they work flawlessly and there's no issues with seals and, operation. I've used ATF and get the same results. The rams on most hydraulic leveling systems are good quality but, are not totally stainless. There is potential for pitting and potential for a tad bit of rusting, IF, they're left out in the open, wet, potentially salty air, for an extended period of time.

We don't and haven't experienced long term stays at any one particular place so, our levelers are not subject to those extended/exposed conditions. They are however, extended for maybe a month or two INSIDE our RV garage. But, the climate control in there is a better better than the outside elements. So, with all that being said, if we were to stay in one place for as long as some of you do or, store it with the Jacks extended for a long period of time OUTSIDE, I'd spray them down with whatever you choose to keep the moist, wet air from them. Then, every once in a while, wipe them off and reapply. Good luck.
Scott

I clean our hydraulic leveling cylinders twice a year using silicon spray. Also lube the slide tracks with slide lube and treat the slide rubber seals with seal lubricant, both twice a year.

dougrainer wrote:

johnhicks wrote:
HWH says to spray with WD-40 and wipe off.

As I stated, cycling the jacks twice a month will be all that is needed unless they get extremely dirty. When retracted, they are immersed in ATF fluid which means you do not have to lube with WD 40 or silicone. Doug

https://www.hwhcorp.com/ml47149.pdf

What will cycling do to help the seals?

Unless the seals are shot the fluid is contained by them, I.E. the wet side is always wet and the dry side is always dry.

It would seem cycling would just expose the wiper seals to that much more debris.

If the MH is moved 4 times a year the wiper seals are used to clean the piston rod of debris 4 times. If the jacks are cycled twice a month the wiper seal is used to clean debris 24 times a year.

My jacks are down for 7 months every year for the last 10 years and I have never sprayed anything on the rams. They extend and retract well every time.

JaxDad wrote:

dougrainer wrote:

johnhicks wrote:
HWH says to spray with WD-40 and wipe off.

As I stated, cycling the jacks twice a month will be all that is needed unless they get extremely dirty. When retracted, they are immersed in ATF fluid which means you do not have to lube with WD 40 or silicone. Doug

https://www.hwhcorp.com/ml47149.pdf

What will cycling do to help the seals?

Unless the seals are shot the fluid is contained by them, I.E. the wet side is always wet and the dry side is always dry.

It would seem cycling would just expose the wiper seals to that much more debris.

If the MH is moved 4 times a year the wiper seals are used to clean the piston rod of debris 4 times. If the jacks are cycled twice a month the wiper seal is used to clean debris 24 times a year.

It helps run a thin film of ATF by the seals and helps keep them "supple". Seals can dry out. There is no such thing as a "wiper" seal. There are lower and upper seals and both contain the fluid. You are overthinking this. The amount of times you operate your jacks is a none issue. They are designed for thousands of cycles. Doug

dougrainer wrote:

JaxDad wrote:

dougrainer wrote:

johnhicks wrote:
HWH says to spray with WD-40 and wipe off.

As I stated, cycling the jacks twice a month will be all that is needed unless they get extremely dirty. When retracted, they are immersed in ATF fluid which means you do not have to lube with WD 40 or silicone. Doug

https://www.hwhcorp.com/ml47149.pdf

What will cycling do to help the seals?

Unless the seals are shot the fluid is contained by them, I.E. the wet side is always wet and the dry side is always dry.

It would seem cycling would just expose the wiper seals to that much more debris.

If the MH is moved 4 times a year the wiper seals are used to clean the piston rod of debris 4 times. If the jacks are cycled twice a month the wiper seal is used to clean debris 24 times a year.

It helps run a thin film of ATF by the seals and helps keep them "supple". Seals can dry out. There is no such thing as a "wiper" seal. There are lower and upper seals and both contain the fluid. You are overthinking this. The amount of times you operate your jacks is a none issue. They are designed for thousands of cycles. Doug

Now I’m quite sure you’re mistaken.

Levelling jacks have springs on them to retract them, they’re one way cylinders, the seals are wet on only one side unless they’ve failed. Every hydraulic cylinder exposed to the atmosphere has a wiper, otherwise the pressure-bearing seal would be exposed to debris from the cylinder rod.

Only the pressure side of the seal ever gets wet otherwise the jack would never hold any pressure and therefore weight.

So now we're in "Angels on a Pin." territory. The latest guidance from HWH is "spray it if makes you feel good; it won't hurt anything."

The point I think is that you've been in position a long time it might behoove you to spray down the jacks with WD-40 or silicone and maybe wipe them down. Or not.

The lower seal is also a "wiper". The upper seal that is always immersed and inside the housing is the seal that fails when the jack leg is slow or fails to retract all the way. HWH and Powergear and RVA Jacks have springs to retract. All others are power down and power up. Like I stated, you just want to overthink and nitpick this issue. Doug

It all depends on the age of your coach. Back in 2001 we purchased a Winnebago Adventurer. At that time HWH was advertising the piston rods were made of stainless steel so no action was needed to protect them.

However around 2008 (not sure of the exact date) they changed to a nickel plated steel rather than the original stainless. At that time they started recommending that if the jacks were extended for long periods they should be wiped down monthly and sprayed with silicone.

It seems like they have changed their procedures frequently over the years, probably in response to the different materials used in the piston rods. Originally they said no WD40 because it attracts dirt. Later they said use WD40 first to clean off debris, then wipe them down and apply silicone as a protectant.

The best course of action would be to call HWH, give them the year and model of your leveling system, and ask what material the piston rods are made of. Different materials require different maintenance procedures.