Loss of 50% of hydraulic power? C/o filters, no metal or dirt in old filters. Power loss after I c/o small hose to track drive motor?
Komatsu pc250lc-6l
So you changed out the small hose to the track drive motor ? That will your travel speed selector from your epc stack, might have air in their pilot circuit causing it to have no power , needs a good run and bleed the air by the sounds of it