Brake fluid in hydraulic system?

pine tree · 01-30-2013, 01:47 PM

In a hurry and in the cold I needed to add hydrolic fluid to my Winnebago Journey HWH hydrolic slide out and jack leveling system. I grabbed the wrong can and added about 1/2 pint of brake fluid to the system. Everything seems to work fine, but I'm concerned the small amount of brake fluid could damage the system.

Do I Have a problem here? Should the system be drained and purged? Or are we good to go?

Pine Tree

mecfd67 · 01-30-2013, 01:58 PM

You should be ok but maybe you can retract the rams completely and use a small pump to pull most of the fluid out of the system resivour and replace with new. This will dilute it even further.. Do this a few times and that would be even better. In a pinch you can use ATF in place of hydraulic fluid.

garykk · 01-30-2013, 02:05 PM

I think you should be OK as long as the tank has hydraulic fluid and NOT ATF as some do. The brake fluid would have a higher boiling point. Brake fluid and ATF do not mix and will settle out.

FIRE UP · 01-30-2013, 02:39 PM

Pinetree,
Well, mistakes are made, it's not the end of the world, besides, that was supposed to happen in December and I missed it. Anyway, while both fluids serve as a hydraulic fluid, they do it in different environments and, have different chemical makeups. They most likely will not "clash" but, the seals and inner non-metallic components may not be too happy with the chemicals of the brake fluid. If it were me, I'd find a way to either drain what's in the reservoir or, bleed as much off, replace as you bleed 'till you think you've evacuated an amount that should rid the brake fluid. Let's put it this way, if it's determined (By someone in authority at HWH) that the brake fluid could be harmful to internal components and that the system should be flushed to limit the potential problems, heck, 5 gallons of ATF or even order up some HWH fluid and flush the heck out of it.

That would be cheap compaired what might have to be repaired/replaced if any damage should occur. I'm just guessing here. Heck, for all I know, you could leave it in there for eternity and nothing will happen.

And YES, you can use ATF. In my HWH manual, it states in BLACK AND WHITE, that ATF can be used. Below is a section from the "Slideout/Service tips manual for HWH".
Scott

Fluid: Unless a leak exists, it is not necessary to check fluid levels. Should you need to add fluid, HWH Specialty Hydraulic Oil is recommended. In an emergency Dexron automatic transmission fluid can be used.

dsbike · 02-02-2013, 03:08 PM

I agree with Fire Up. One question I do have is, is the brake fluid synthetic or Dino. Dot 5 is synthetic 3&4 are not. The synthetic is much more tolerable on seals and metals. It also does not attract moisture. The non synthetic may deteriate yours seals in the system rather quickly and will get moisture ( water) . The big million dollar question is, will the hydraulic system tolerate any kind of brake fluid.

I would drain, flush , and replace the fluid with proper fluid if it was mine.

Also while on the subject of brake fluid, do not add non synthetic dot 3 or dot 4 to a dot 5 brake system.

mrschwarz · 02-02-2013, 05:59 PM

If I remember correctly, the rubber seals in the system aren't going to like brake fluid. In the case of brake parts, if you put them in hydraulic fluid, they swell up and will fail.

I am not sure if the same is true the other way around. If the hydraulic system expects ATF and you added brake fluid, I would check with an expert. You may be able to avoid an expensive repair if you tackle it sooner rather than later.

1ciderdog · 02-03-2013, 09:33 AM

As a thought have you considered calling HWH to ask them about the concern?

HeapBigEngin · 02-03-2013, 01:02 PM

Bummer, for sure. As others have suggested, call the manufacturer(s). I would be VERY surprised if they don't recommend that you drain/purge/refill the system. I would do that if only for peace of mind. The concern I would have is internal seal/'O' ring compatibility with brake fluid, even a minor amount. Although typical hydraulic brake systems have neoprene/specialized rubber seals and "O" rings, the seals within your hydraulic system may be brake fluid intolerant. Just don't know....but the manufactuere should.

Pleas let us know how you make out on this....it will prove helpful to many of us. Thanks....and good luck!

wa8yxm · 02-04-2013, 10:26 AM

There are two main types of brake fluid,, One you'd now have a major problem.. The other,, Not so much.

If you are worried flush the system and re-fill.. NOTE: This is a normal maintenance procedure in any case and likely over due for it.

pine tree · 02-06-2013, 06:59 PM

Hi All,

Thank you all for the helpful response and In information. Arrived in Santa Rosa NM this afternoon and changed out the Hydrolic fluid in the jack/slide system as you recommended. Did this before I lowered the jacks and put the slide out. Bought a little hand pump [sort of like a grease gun in reverse] and drew all the fluid out of the tank. Came to exactly 1.5 gallons of not very clean looking stuff.

I know there may be a very small amount of brake fluid in the lines remaining from the one or two times that I activated the system after putting in the brake fluid, but I have confidence most was in the tank. After all I only put 1/2 a pint in.

Anyway the system worked perfectly after the change. Not a sign of a leak anywhere.

Oh, I found the brake fluid bottle and it is "Type 3" special for disk brakes. I hope that's the good stuff.

This all went so well [the change] I may do it one more time after I use the system a couple more times. What do you guys recommend?

Thanks Again,
Pine Tree

Petro · 02-07-2013, 08:18 AM

pine tree;

I believe you made a wise decision. That is what I would have done. The brake fluid issue aside I think it was good to put some new fluid in the system.

Don

dirko · 02-07-2013, 10:38 AM

Hi Ho: I also think you made a good choice. For what it's worth, HWH hydraulic fluid is simply Dexron ATF without the red dye. If you don't care about it being red, just use Dexron. I think that they say it has to do with a red stain if the system leaks, but I think the real reason they use undyed ATF is so that folks will pay more for their ATF without dye.

I have verified Dexron with HWH. It isn't my statement, but theirs.

Petro · 02-07-2013, 11:39 AM

dirko is correct on the HWH oil. When I was at the HWH factory I was told the same thing. I have always used Dexron ATF in my HWH system.

Don

two2go · 02-07-2013, 01:38 PM

Interesting thread. When I was a poor college boy, my '53 Dodge auto transmission leaked so bad, I bought ATF by the gallon. I could get about 100 miles per quart, and didn't dare park on anyone's clean driveway. A mechanic told me to put in a can or two of brake fluid for a quick fix. I did and it worked like magic. I didn't have to add any more fluid, and I drove the old Dodge another year without any problems until I traded it for a Corvair. Then I had problems, but that's another story.