Loader hydraulic issue

[hyndsight]

'97 1620 w/7108 loader:
I have resealed bucket cylinders, checked and or replaced quick couplers, and now replaced the loader control valve........
Bucket roll circuit will power down only, when I try to roll up, it only makes the engine bog. At this point I can swap hoses around to make it go up, or swap loader arm hoses for bucket hoses and it works fine, (then arms act the same way). Also, when I disconnect hoses, hydraulic pressure remains rather than bypassing, making it very difficult to re-attatch the hoses.
Any ideas would be greatly appreciated.........thanks, Tim.

 

[Greenblood2011]

May sound stupid but make sure you haven't hooked the hoses wrong at the quick couplers. Maybe you have a boom and bucket function switched? How did this problem first start?

 

[hyndsight]

No, tried every combination with hoses and all it does is move the problem around, so I'm thinking it has to be at or before the lcv, (which is why I replaced it).
Problem started originaly with very slow bucket up, eventually no bucket up.....

 

[Greenblood2011]

You need to get some pressure gauges and take some tests, it could be a bad relief valve. Let me know what you find

 

[J_J]

If the old valve did the same thing, and the new valve is doing the same thing, then your hoses to the valve/cyl are not correct. It is not hard to verify. Remove hoses from the cyl's and activate one of the levers to up/fwd, mark the hoses, and do the rest of the hoses, by placing the lever in the position you want to check. .

Use a plug in pressure gage if you have one.

The engine is bogging down because you did something wrong. A relief would go off and protect the engine.

Do you have the hose from the pump going to the IN port

 

[hyndsight]

OK, right now ALL hoses are in correct position.....(and when this problem first presented itself I had never removed a hose.
When I disconnect the hoses at the loader arm, (beyond the quick connects), I get normal operation (fluid coming from one hose or the other depending on where the control is operated) from both arm hoses and the bucket DOWN hose. When I opperate bucket up, I get a steady stream of fluid coming from both bucket hoses.

 

[Greenblood2011]

I'll still think you need to pit a gauge on it and verify you the correct pressure to lift the bucket... You might have enough to roll the bucket but not raise it. You can by a gauge and a quick coupler for about $20. I would buy one for 3000 psi that should be plenty high enough.

 

[jinman]

This really sounds like something has plugged/partially clogged the bucket raise line between the joystick valve and the quick connects. It seems you've isolated everything else. This may not be it, but it should be easy to check and verify.

 

[TraderMark]

This is your problem.

When I opperate bucket up, I get a steady stream of fluid coming from both bucket hoses.

Now we have to figure out what's causing both ports to pressurize at the same time.
Does the new valve have "regen" feature?

Mark

 

[hyndsight]

This is your problem.

Now we have to figure out what's causing both ports to pressurize at the same time.
Does the new valve have "regen" feature?

Mark

Yup, the "new" (used) valve is actually an identical one from another 7108 loader (symptoms identical before and after).
I'm a little unfamiliar with the whole power beyond circuit, but it seems unlikely that the problem is on the tractor side of the valve as it is only affecting the bucket spool?
I havn't guaged anything yet, but I'm not sure what that would prove given the symptoms.....