Leaving Implements Raised - Bad For Hydraulic System?

[Snowlan]

The hydraulic system is not loaded when an implement or loader is elevated and stationary, only the cylinder holding the implement has a load. The cylinder is unaffected whether the hydraulics are running or not, until a control lever is moved. Likewise for the hydraulic pump, there is no load on it beyond system resistance until a lever is moved and oil put to work through the valve. Getting on and off the tractor as you have described will have no impact on the equipment

It is all about safety and leaving stored energy unattended.

 

[Snowlan]

The hydraulic system is not loaded when an implement or loader is elevated and stationary, only the cylinder holding the implement has a load. The cylinder is unaffected whether the hydraulics are running or not, until a control lever is moved. Likewise for the hydraulic pump, there is no load on it beyond system resistance until a lever is moved and oil put to work through the valve. Getting on and off the tractor as you have described will have no impact on the equipment

It is all about safety and leaving stored energy unattended.

Sorry, I need to correct myself on part of that statement. For these simple tractors that we are dealing with (I'm sure larger equipment becomes more sophisticated), there is no position control on the FEL so a loader that sags while it is shut down will also sag while it is running. It's just more noticeable when you park it and can see the relative movement over extended time. As I was thinking about what I had written previous, it occurred to me that most of the tractors beyond the sub compact size have position control on the 3 point hitch and I haven't received my tractor yet to see how that is designed. In that case if the hitch has a load and sagged while shut down, I would think the feedback will demand oil as soon as the pump starts to turn again to restore the position that the command lever is calling for. However, if that is happening in 7 minutes, you have issues that probably need repairing.

 

[John0829]

So this brings up another question. Do hydraulics eventually fail because of use or age?

Both, use causes wear even though everything is in oil, first a hydraulic system is not filtered as finely as the engine is so there are more particulates floating around in there. Then add to that the heat generated which causes seals and packing to harden and finally most hydraulic systems tend to get over looked when it comes to routine maintenance.

 

[BackRoad]

Good stuff, greatly value the responses...and thoughtfulness.

Interesting results from self monitoring after posing the question. I was on and off the tractor again today, about 6 hours of active work...downed trees, slash and brush pile work.

Tried to be more consistent in lowering the bucket and 3PH when shutting off the tractor for the work described initially.

Had to laugh after my neighbor wandered by to chat. I sat on the tractor, and shut it down so we didn't have to shout...and yup...didn't lower the grapple or ballast.

Same thing happened again when my wife drove by and stopped to update, after returning from the quilt shop.

It looks like lowering the FEL and 3PH is the way to go for safety...(although very little risk of a roll away tractor on my property).

And my main concern - it seems no real damage done to the hydraulics if they are left under load with the tractor off, occasionally during work activity...or maybe while being neighborly!

Thanks everyone who contributed to the discussion.

 

[LD1]

Actually in the situations you describe......leaving the implements up, is probably "easier" on the hydraulics than the constant raising and lowering.

Think about the seals in your hydraulic cylinders. They dont last forever. They have a finite life span. And what wears out seals and cylinders is cycling. Sure it takes thousands or millions of cycles to wear out a seal/cylinder.......but if everytime you got off/on the tractor you cycled them up/down.....stands to reason that they will wear out faster rather than just sitting static and holding a relatively light load.

 

[Blue Mule]

My father is a 45+ year career heavy equipment mechanic. He gets irritated if I leave the 3-point hitch up on the tractor with an implement attached when I park it, and he's specifically cited mechanics and not safety as the reason.

So in order to keep him happy I always drop the implement when I get off the tractor if I'm working around the property.

 

[Bob Rooks]

The question is if anyone from the TBN Brain Trust is aware - conclusively (not conjecture) - whether shutting off a tractor while the hydraulics are loaded is verified to be any more adverse for hydraulic system components, compared to what they receive during standard duty cycles with the tractor operating.

You can answer your own question if you understand Pascal's Law. Otherwise, any answers you receive here may be totally subjective.

 

[daman1]

I've seen seals tend to leak when there's pressure on them Implement weight raised I always relax the Hydraulics when I'm done, just what I do.

 

[Rebeldad1]

Its kind of like leaving a heavy load in your pickup. Its ok but maybe not so great. I always leave equipment parked with any load on the ground. It was SOP everywhere I worked construction at.
Ever watch your tractor move /raise up when you lower your load to the ground?

 

[CoyPatton]

Is there any real evidence (kindly not seeking opinions)...

that leaving the 3PH or the FEL raised with the tractor not running places extra stress on the hydraulic cylinders or seals?

As you later described what you are doing, there is probably only the safety issue that has been expressed by many. One additional safety concern would be the tractor rolling and the potential safety items related to bodily injury and equipment damage.
i am assuming that the time period of you being off the tractor is short term, but ling enough you did not wish to leave it running. For long term leaving these in the air, internal seal damage allowing the cylinders to leak down fairly quickly. This is even more likely once the seals wear, potentially leading to quicker failure.