Can't hook up rear hydraulic line

[mattlsR4020]

Hi Everybody,

First post. I bought an LS R4020 TLB 47 hp, back in October. Haven't done much with it yet, but I have taken the hoe off twice. It comes off easy but when I hook it back up, one of the hoses seems to be pressurized and won't depress the center nipple when mating with the hookup on the tractor. I turned it off, wiggled all the joysticks. I had to tap it with a hammer to remove the pressure. What did I do wrong?

 

[Wnc3]

Here is a suggestion:
Before you disconnect the hydraulic lines,
Turn off engine, move all related levers to relieve all pressure, then uncouple.
Then don't move any levers on the hoe until you reconnect.
If you need to relieve again, use a wrench to relieve the pressure slowly a the fitting. (you won't get sprayed with oil trying to press the end of fitting)

 

[Soundguy]

did nuttin wrong.. outside temps and whatnot.. relaxing cyls.. etc can cause the presusr ebuildup.

exercising the sticks prior to shutdown helps.. but the hammer tap thru a rag works too..

 

[mattlsR4020]

Thanks for the tips. I think you may have hit on something when you said "not to touch any levers until you reconnect." I'm wondering if dropping the boom/dipperstick (after disconnecting), somehow 're-pressurized' the line? I'll try it again w/o moving levers after disconnect.

 

[Gary Fowler]

Just shut down your tractor and move the levers to all positions, this will equalize the pressure in your tractor. The problem is likely in the male hose connects that have built up pressure from temp change. You will have to relieve that pressure. I used to do that on the farm by just tapping them against the tractor frame. JD had a coupling that you could hook up under pressure which was great invention. I havent seen that on a CUT so get out your rag and rubber / brass hammer as suggest and whack that tip on the connections. There shouldnt be a lot of oil come out, buy you will have to get it to neutral pressure before you can hook it up.

 

[murphy1244]

Hey guys , Is the preasure coming from the hoe or machine?? I'm thinking install a ball valve on the side of where the preasure is.

 

[J_J]

In a closed circuit, temperature variations may cause a pressure build up and require you to relieve the pressure . Just tap the ball in either of the QD.

You could add a small 3000 psi ball valve before the QD on the BH side, and just open the valve when you have difficulty. Don't forget to close the ball valve when you are connected.

 

[Soundguy]

yep.. an annoyance if anything.. but not a problem...

 

[Wnc3]

Thanks for the tips. I think you may have hit on something when you said "not to touch any levers until you reconnect." I'm wondering if dropping the boom/dipperstick (after disconnecting), somehow 're-pressurized' the line? I'll try it again w/o moving levers after disconnect.

I think it does....

 

[Chilly807]

I had a couple of QDs on my rear blade that refused to re-connect a couple of weeks ago. I'd taken them off when it was blistering cold and a warm day when I tried to reconnect. Even tapping the nipples didn't do the trick, I had to loosen one of the fittings.

Sean