I bought a used L4400D last weekend and am getting to know it a little bit. I checked the rear site glass this morning, and the fluid level was good, and the fluid was clear. After using the FEL to push some brush piles for about two hours or so, when I checked the site glass again, the fluid is now kinda milky looking. I'm guessing it's not supposed to do that?
Milky hydraulic fluid?
- Thread starter Witchgrass
- Start date
Unless it is lightly used, I would be replacing all fluids and filters on your tractor, unless you have proof it was done recently. Milky colored oil normally indicates the presence of moisture. I would look at changing it.
85Hokie
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I'LL double up on what Mike said ......seems like you got a little water in the mix. Do as he says!
X2 on water and oil change!
If you crack your drain plugs after sitting overnight, the water will have separated and be on the bottom, also don't forget your rear axle drain plugs if you have them.
If you crack your drain plugs after sitting overnight, the water will have separated and be on the bottom, also don't forget your rear axle drain plugs if you have them.
Ok,so I've a new filter already. Do I just need to drain and refill, or do I need to flush, then refil. Also, where did the water come from. We had a lite Rain a few days ago, but the tractor should be mostly sealed up, right?***129300;
Milky can be aerated, or contaminated, by different things. Water is common, when washing the machine water gets in around breather rubbers that have shrunk over time, and pressure washed into the breathers, moisture (water vapor) is drawn in from hot cold cycles in the air over time, then condenses to liquid when cooled and drops to bottom of oil pan.
Cracked or loose filler plug.
Drain on level surface and think about cylinders etc as well. Depending on the contamination level a couple of changes over time may be necessary. Some may consider using a cheap oil as a first flush, then use for a while then re-change with a better oil.
Cracked or loose filler plug.
Drain on level surface and think about cylinders etc as well. Depending on the contamination level a couple of changes over time may be necessary. Some may consider using a cheap oil as a first flush, then use for a while then re-change with a better oil.
North Idaho Wolfman
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Could be sucking air on the suction side of the pump too, so check the suction line for loose fittings or possible leaks.
All true, and certainly worthy of consideration. My previous L3410 fluid would appear milky / aerated from day one after an hour or so of use.
On a side note, prior to buying the tractor,I noticed that there was hydraulic fluid on the bottom side of the tractor but everything else looked ok. Yesterday after finding that the site glass looked milky, I noticed that the leaking hydraulic fluid is actually coming from underneath the seat. I assume this is coming out of a breather tube. Maybe it's got water in it and the hydraulic fluid is being pushed out the breather?
Does the transmission and hydraulic system share the same fluid? I'm seeing 10.6 gallons of fluid for the system. Is there a certain rations of the hydraulic oil?
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Russell King
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And all the fluid goes in the same sump - except for front differential on 4wd
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Thanks guys, I'll pick up some new Hydraulic fluid tomorrow. Am I going to have to flush this a few times, or will a drain and refill be good enough?
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After letting the tractor sit overnight, pull/drain each bung for a second into a bucket and replace, then pour that fluid into a clear container and see what you have to deal with.
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Ok. Gonna do this this evening when I get home. Hopping for the best and get it all out the first time. Not sure how sticky the milky formula will be. Hope it all drains out real good.
While I and most others would recommend a fluid change when you buy a machine, (especially if you don't have service history), taking a sample from the drain bungs should show contamination if you have it, so then you can address that issue, work out how and where it came from. If you don't sample first, it may be difficult to see the contamination in the bulk oil if you drop it all at once.
You also may have no contamination, just aerated oil, and have a suction line issue as NIW mentioned to check for.
You also may have no contamination, just aerated oil, and have a suction line issue as NIW mentioned to check for.
I stopped by the local Kubota dealer today to get a few nuts and bolts needed to replace one of the side panels on the hood. I ended up talking to the mechanic about the milky color I was seeing. He then showed me a new site glass that he pulled out of the package and asked me if it was similar to what I'd seen on mine. He pointed out that on the back side of the site glass is an offset white cap. This white cap helps to actually see the level of the fluid inside. He said this may be what I was seeing. He suggested that I pull one of the plugs and see if there is ANY water in it. I went home and pulled the front plug. Nice honey colored oil came out. Yay!!!, no water at all. Probably lost about a quart of oil. Gonna plan on topping it off for now, then do a full fluid change in a few weeks.
As mentioned previously, take a sample from ALL bungs to be sure. YMMV
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