10 Ton Floor Jack will no longer release its load

[ratchetbender]

Delco 10 Ton Jack Model 34702. With the lowering valve open, It will no longer release its load.




Is this made by Hein-Werner ? If so what is the equivalent Model Number, - X-10 ?

 

[Hiball]

It’s Not made by HW, it’s a import. Does it release under load? If not I would check the linkage to make sure everything is connected.

 

[ratchetbender]

The linkage is working properly. Peraps I'm asking which ball and spring to disassemble.

 

[Hiball]

Is the jack under load currently? I’ll ask again, Is the jack not lowering under load or while light? Lift arms don’t generally stick in the up position under load unless you have serious binding issues internally or have filled the unit while up and it’s locked up. If the release is operating correctly and knob feedback is transferring to the release, then that would be the first place I would investigate.

Is that even the correct diagram? Looks HWish too me, I’m fairly certain your jack is a single piston/stage, so no speed/pressure valves.

I would not just randomly start opening valves, just asking for problems and losing components.

Outside of that, if investigating the release doesn’t find the culprit. It will require a tear down to make sure it’s not something internal binding up or **** plugging the release port from the inside.

 

[ratchetbender]

I can't release pressure to lower the tractor I was servicing. I suspect that over a time of not being used, water is in this fluid. Rust?

 

[Hiball]

I can't release pressure to lower the tractor I was servicing. I suspect that over a time of not being used, water is in this fluid. Rust?

You need to find another method of getting that tractor down, removing valves or doing anything to the hydraulic unit while under load is extremely dangerous for various reasons.

 

[TeenagerThatLikesFloorjac]

I can't release pressure to lower the tractor I was servicing. I suspect that over a time of not being used, water is in this fluid. Rust?

If your jack is on a surface that it cannot easily roll on, and is wedged in place, even if you open the release valve, the lifting arm won't come down. The jack needs to be able to roll back for it to lower the load.

I have no idea if this is happening in your case, but it has happened to me before while using a small trolley jack: one of the rear casters got wedged in a crack and it wouldn't lower the car.

I hope this post helps, good luck

 

[Provincial]

+1 on using another jack or other method to raise the tractor off this jack. Once the load is relieved, if this jack does not come down you can proceed with trouble-shooting.

Get the jack safely out from under the tractor and report back.

 

[ajchien]

The linkage is working properly. Peraps I'm asking which ball and spring to disassemble.

I believe that valve diagram comes from the 4 ton HW GG, which is not the jack pictured in the original post.

 

[gungatim]

LGR

 

[Mallen]

You need to find another method of getting that tractor down, removing valves or doing anything to the hydraulic unit while under load is extremely dangerous for various reasons.

I would also note, if you tried to release the jack,band it did not come down, assume it could let go at any moment and act accordingly. (Like if a piece of crud was blocking a passage, once you open the valve, that crud could blow out of there and the whole thing could drop on you while you were under there fiddling with or inspecting the jack.

 

[Hiball]

I would also note, if you tried to release the jack,band it did not come down, assume it could let go at any moment and act accordingly. (Like if a piece of crud was blocking a passage, once you open the valve, that crud could blow out of there and the whole thing could drop on you while you were under there fiddling with or inspecting the jack.

It goes without saying that placing ones body under the load in a attempt to manipulate the valve system/repair, in a attempt to lower the jack is a bad idea. It can cause bodily injury, property damage and probably the worst feeling in the world would be to cause harm to someone else due to your personal actions.

Outside of being crushed, pulling a pressure cap and allowing upwards of 5k psi’s of fluid to exit the cylinder thru the tiny valve passage and out the topside of the jack will certainly drop the load at a near uncontrollable rate all the while spraying high pressure in multiple directions.

It’s just not a good idea to say the least, If the Op doesn’t have a option to get the load up and down, Run to HF/farm store and buy the cheapest bottle jack to cover your Lifting needs and reassess the situation from a better place.

 

[ratchetbender]

As you see the "down" valve shaft is turning as it should.
It is no longer holding up my tractor.
The jack will go up further easily, but not down.

 

[Hiball]

As long as nobody added oil while the lift arm was up, it’s gonna require a tear down. I’ve seen rusty linkages/center pins slow things down, but normally a load can overcome the resistance. Maybe pull the fill plug and see what happens.