what could be problem if fast/slow switch makes no difference to speed of hydraulics. all solenoids seem to working ok. seems to be operating in slow mode
The HSC solenoid operates the unloader valve in the top of loader valveblock the unloader could have a split seal or be stuck open dumping pump 2 to tank. I would advise connecting 400 bar gauges to pump 1 and 2 to check operation of MRV and unloder valve.
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