komatsu pc 200 lc-8 swing and trame problem

if your excavator has a track almost dead until you hit a function and swing is slow ,I hope this helps u out. This it may help u find your problem.If one track is very slow and the other one seems faster than normal and swing is dog slow wen engine is at full throttle.Back throttle to around half way if the swing speeds up like normal and you can hit travel hit the slow track fully engaged hit another function if the track works like normal . The problem is your merge flow valve .You remove the valve dismantle it give it a good cleaning replace the poppet valve and spring between this valve and the main control valve.Reinstall with new O-rings.hope u don't have to replace it this thing cost like 9000.dollars.the dealer will not rebuild this valve you have to do it your self. the valve is kind of heavy and hard to get out. Just need to remove the firewall from the engine compartment plus the line from the turbo to the aftercooler. remove a few hoses couple sensors and your there. good luck