Yanmar SA424 possible water contamination in Hydraulic Fluid

[rScotty]

Quick update: I waited until the warmest part of the warmest day (a couple weeks ago now) and the tractor started up. I added an anti-gel rich fresh diesel to the tank and she's running as good as ever. As for the hydraulics; I put 1.6 bottles of Seafoam in the hydraulic tank (the rest in the fuel), checked that the level was full, then started it up. Slow, shuddering hydraulics that didn't get much better as they warmed up. Then I checked the sight glass...off the glass low. I realized that cycling the cylinders by hand had the desired effect of draining more contaminated fluid, but also required a gallon or so more fluid than the stated capacity. Oops. I made up the difference with fresh diesel and eventually it seemed to get all of the air out of the system. Everything is running great now! I'm grateful for the knowledge of this community.

Now the next step. I figure my hydraulic system is 4/5 mildly contaminated hyd fluid, and 1/5 diesel. I've warmed it up thoroughly a couple of times by pulling the kids around the neighborhood on sleds, then cycled every cylinder a few times to mix everything up. I imagine that the Seafoam has done its work right away, or is there benefit to leaving it for a bit? I plan to warm it up one more time, lift all 4 corners off the ground, drain the hyd system again, filters included, cycle each cylinder by hand again, this time I'll also try to rotate the drive motors and steering cylinders. I'll re-fill with fresh fluid and call it good.

I intend to use at least some low viscosity HyGard. Because this machine maybe working hard in summer months, I'm inclined to mix the Yanmar specified viscosity with the low stuff, perhaps in a 2 to 1 ratio. Is this overthinking it? Any reason not to mix fluids?

I doubt if anyone can tell you whether or not to mix the fluids, since we don't have any idea what is really in either one. But I have had JD service managers I trust say you can mix low and regular viscosity HyGard. In fact, one called the JD tech dept. and asked as I stood there.

SeaFoam is just trade secret petroleum oils - which could be anything from gasoline to gear lube - plus a slug of isopropyl alcohol to bind to water. Alcohol can only bind to a small amount of water so it probably accomplished whatever benefit it had immediately. Your seals are nitrile i.e. Buna-N which is fairly resistant to iso-alcohols, so a little bit is probably OK- but I'd get it out of there or dilute it.

HyGard is not expensive. Your plan sounds good to me. I'd run it for awhile and then drain some off, let it settle in a glass jar for awhile and see what it looks like. Stratification separation of liquids is generally figured to take a month settng in a quiet place. A few drops of HyGard on clean ink blotter paper might show you something too. It used to be a common test. There is also a "sizzle test" for water in oil that you can do with a few drops of sample. All three of those water-in-oil tests cost nothing but are highly subjective. If you send your oil off for analysis, they will probably do the sizzle. You can teach yourself to do that as well as the pros do.

rScotty

 

[Hulaballoo]

I doubt if anyone can tell you whether or not to mix the fluids, since we don't have any idea what is really in either one. But I have had JD service managers I trust say you can mix low and regular viscosity HyGard. In fact, one called the JD tech dept. and asked as I stood there.

SeaFoam is just trade secret petroleum oils - which could be anything from gasoline to gear lube - plus a slug of isopropyl alcohol to bind to water. Alcohol can only bind to a small amount of water so it probably accomplished whatever benefit it had immediately. Your seals are nitrile i.e. Buna-N which is fairly resistant to iso-alcohols, so a little bit is probably OK- but I'd get it out of there or dilute it.

HyGard is not expensive. Your plan sounds good to me. I'd run it for awhile and then drain some off, let it settle in a glass jar for awhile and see what it looks like. Stratification separation of liquids is generally figured to take a month settng in a quiet place. A few drops of HyGard on clean ink blotter paper might show you something too. It used to be a common test. There is also a "sizzle test" for water in oil that you can do with a few drops of sample. All three of those water-in-oil tests cost nothing but are highly subjective. If you send your oil off for analysis, they will probably do the sizzle. You can teach yourself to do that as well as the pros do.

rScotty

Hadn't heard of the sizzle test, but it sounds like a good idea, I'll give it a go. Early in this thread, a member mentioned a hydraulic filter cart that could polish the water out of the oil. Although I didn't find one where I live, I just stumbled across this method that was posted on a waste oil burner FB page. I remember my HS science teacher freezing water as it boiled... His is a brilliant solution, though perhaps not worth the effort in my particular situation and the amounts of fluid that I'm dealing with.

 

[nyone]

I had a 1950s ford 60hp tractor that had so much water in the trans it wouldnt move when cold. That tractor still works today. Your machine will be fine.