Does it matter if FEL is attached when changing hydraulic/HST fluid and filters?

[RoyK]

Title is pretty much my question. Also, should FEL be raised (to help drain old fluid from it, cycling control lever while draining) or down on the ground when I pull the drain plug?

 

[Dwellonroof]

I wouldn't think it matters , you are not draining the fluid from the cylinders only the reserve/holding tank.
I would keep it lowered though just in case.

 

[Slowpoke Slim]

I would never open or drain a hydraulic system with part of it (boom or FEL) extended off the ground. Just a recipe for a safety incident.

 

[MHarryE]

I don’t understand - attached or disconnected, there will always be oil in the loader cylinders that don’t get changed.

 

[mikester]

Title is pretty much my question. Also, should FEL be raised (to help drain old fluid from it, cycling control lever while draining) or down on the ground when I pull the drain plug?

Hard to drain ALL (or as much as you can) the fluid when you fill the cyclinders with oil to raise the loader. You want all your cyclinders fully retracted where possible. Safer too.

 

[rScotty]

Title is pretty much my question. Also, should FEL be raised (to help drain old fluid from it, cycling control lever while draining) or down on the ground when I pull the drain plug?

You've put your finger on one of the problems with changing HST/hydraulic oil - that there is quite a bit of old oil left in the system because only the sump gets drained.

The other HST/Hydraulic concern isn't about oil changes. It comes about when hooking up someone elses attachment to your hydraulic system. Think about rentals. Who used it that attachment last and what kind of fluid is in there?

To get back to the question, raising the FEL off the ground won't help much and I don't know of anyone who does it that way - although this thread may bring a few forward.
Hmm.... I can see that if we raise the FEL and then use the control valve so that gravity progressively first rotates the bucket and then lowers the booms that you might could get a little more oil out - but it would be tricky & dangerous. Things could fall all of a sudden plus you get air into the system which can be hard to get out. I don't know of anyone who does it that way. The usual compromise is to change oil with all the cylinders in their shortened mode. A cylinder when collapsed holds somewhat less oil than when extended due to the volume taken by the steel ram.
Luck,
rScotty

 

[mcfarmall]

I don’t understand - attached or disconnected, there will always be oil in the loader cylinders that don’t get changed.

You are correct. As long as your sump isn't contaminated per se, there's no need to fret over the amount in the FEL that remains. Unless you're super **** about getting every last drop out of the machine then you will have a major disassembly and cleaning job ahead of you.

 

[MaineGuy1]

You are correct. As long as your sump isn't contaminated per se, there's no need to fret over the amount in the FEL that remains. Unless you're super **** about getting every last drop out of the machine then you will have a major disassembly and cleaning job ahead of you.

Exactly. It is all about the volume. The PPM of contamination in the FEL or other implements will be mixed to negligible numbers when the larger volume is cleaned.

 

[Bavarian]

Just make sure when refilling the reservoir, the level has to be correct when the loader is diconnected from the tractor and stands on it's own support.

I had a similar idea to flush the lines and cylinders before the old oil mixes with new. It can be done, but I didn't.

 

[MHarryE]

Most Kubota owners don’t know there is now a UDT HD. It is used only in the M7 with KVT. I’ve had my dealer check - no, it’s not permissible to mix with Super UDT2, which is what I use in my L6060. The UDT HD is not allowed in the L6060. You wouldn’t think that would be a problem because I’m never going to pull the large equipment for the M7 in the field with my L6060, but if I want to move the disc or cultivator into the yard and position to work on, it’s much more nimble with the L6060. Drop the wings and lower the wheels - about 10 gallons of fluid from those big cylinders gets exchanged. I can avoid that by only using the M7 for the large equipment but the grapple gets used on both. Small cylinders but lots of cycles.

But back to oil changes - in design we estimate up to 40% remains. Draining cylinders and hoses and the like only makes things worse by creating an entry point for contamination

 

[Texasmark]

I don’t understand - attached or disconnected, there will always be oil in the loader cylinders that don’t get changed.

Yepper, bidirectional cylinders have fluid on both sides of the ram. Only way to get it all out is to dismantle the hydraulics piece by piece. Besides, considering the volume of the FEL system vs sump, not that big of a deal.

Where the concern comes in is when you have hydraulically driven implements that you use on different tractors. That's where the problem lies...old implements having been driven by old tractors not requiring today's lubes, or full of water from sitting out for years in the weather.......

 

[Tennsawdust]

Yepper, bidirectional cylinders have fluid on both sides of the ram. Only way to get it all out is to dismantle the hydraulics piece by piece. Besides, considering the volume of the FEL system vs sump, not that big of a deal.

Where the concern comes in is when you have hydraulically driven implements that you use on different tractors. That's where the problem lies...old implements having been driven by old tractors not requiring today's lubes, or full of water from sitting out for years in the weather.......

Exactly. With double acting cylinders there is no change in volume held regardless of position. Some older tractors used single acting cylinders on the loaders and there they recommended checking the fluid with all cylinders extended (loader up, lift up) so that you filled high enough to accommodate the full system volume required to operate everything.

 

[ericm979]

Unless it's a cylinder with the rod coming out at both ends (like are used for steering), the rod takes up some oil volume when the cylinder is compressed. Putting the loader down and curling the bucket would put the rods in the cylinders and take up that volume so there's a little more oil being changed. But it's a small difference that's not worth bothering about.

 

[RalphVa]

You're not draining fluid from the lines, only from the HST chamber. The HST fluid doesn't wear out or get contaminated (if filter is working) in the lines either, to need any changing.

Ralph