Cat 320c left travel weak

Hi, i have a trouble with a cat 320c prefix PAB, the left track is weak, the travel motors are good and the swivel too, in a three revolution test in a low speed the left track makes three revolution in a 39 seconds, the right track makes three revolutions in a 30 seconds, but when I do other movement at the same time like a stick or bucket the left track speed increases.

I suspect negative flow control trouble, i measure the pressure in a left a right NFC lines, when i move the travel lever of the right track to full travel position the pressure in a right NFC line down from 350psi to 30psi , and the left NFC line is 350psi, when i move the travel lever of the left track to full travel position the pressure in a left NFC line down from 350psi to 30 psi, but the right NFC line pressure increase from 350psi to 650psi :eek:, is this normal?
when a move left a right travel lever, left a right NFC lines pressure down and the speed for a left track increases.



I remove the right regulator and disassemble and find this:

the clearance of the spool is no normal for me.
https://www.youtube.com/watch?v=JN34THHUWrE

Is normal this fault? Is necessary other test?

I appreciate your comments, thanks in advance. :)

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Cat 320c left travel weak