Bleeding air or something else?

[RNeumann]

I have a FEL that has had weak curl since new. It now has about 50 hours on it. The dealer added hydraulic top, tilt and rippers and third function- he was into the hydraulics.
In my diagnosis I cycled everything several times- grapple, top/tilt/rippers, FEL lift and curl. I also swapped the curl and lift QDs which improved the curl. Once I switched everything back- so loader control valve worked normal- the curl was again weak. I then changed both curl cylinder QDs- still weak. Today I took the hoses off the curl/retract side of the cylinders to look for debris and everything looked good. I then used the tractor for a few hours doing mainly box scraper work- maybe 6-10 buckets of dirt in that time.
I stopped for lunch and noticed one of the new curl QDs was leaking. It was a good enough leak that it left an almost continuous trail of fluid- I'm guessing it puked a quart or two before I found it. I put another new QD on and BAM no more weak curl!
With two different QDs and an inspection of both I am sure it wasn't two plugged QDs. That leaves two (maybe more) options. I'm wondering if this sounds like the leak allowed a bunch of trapped air to escape or did a chunk of debris finally break free? The QD that was replaced today was also changed a month or so ago- so it's been apart before.
At this point I'm not complaining but still scratching my head.
Thx for the insight!

 

[Texasmark]

I'll go with the debris breaking free. With your cycling, and assuming you meant fully max one direction to max the other, several times, that should have removed the air or at least improved things enough for you to continue till you were satisfied that you had it all out.

 

[RNeumann]

Thx for the reply. Yes everything was cycled fully at least 20 times. Plus almost 50 hours of use- FEL plow with hydraulic angle and box in the winter and box, grapple, bucket and forks in the summer.

 

[LD1]

No idea and at this point, all anyone can do is guess.

Without ever having a pressure gauge put on it......

Hard to believe that a little debris / blockage would cause it to be weak. Slow, Yes as it would impede flow, but a blockage should still allow full pressure be built, just slower.

 

[RNeumann]

No idea and at this point, all anyone can do is guess.

Without ever having a pressure gauge put on it......

Hard to believe that a little debris / blockage would cause it to be weak. Slow, Yes as it would impede flow, but a blockage should still allow full pressure be built, just slower.

Sorry I forget to mention that. I pressure tested every QD- FEL, third function and the top, tilt and rippers. 2200psi at idle (no change with RPMs) which is spec for my machine.

 

[RNeumann]

Sorry I forget to mention that. I pressure tested every QD- FEL, third function and the top, tilt and rippers. 2200psi at idle (no change with RPMs) which is spec for my machine.

And correct- not noticeably slow. Just weak.

 

[oldnslo]

A partially blocked QD in the return line during curl would add back pressure which would reduce the curl force while moving. Once static or moving slow the force should in theory increase.