2001 773 500k Aux hyd problem

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Nov 24, 2022
This is a 773 500k 2001 skid steer with ahc controls. I have a problem with the grappler attachment. I start the loader and push the hyd button to vari flow or max flow and then on the right lever hit the thumb switch to the left and the grapple opens and then to the right and the grapple closes and push to the left again and nothing happens push to the right and you can hear the loader load down. turn loader engine off and start up again and it works the same way again. I looked at the schematic on this and the lever for the thumb is a pwm switch i checked the resistance on it and it seem good on both ways. I also switch the solenoids around and the same thing happens again. I even took the solenoid stem out to make sure the orings look good and cleaned it put back same thing again. I checked the coil resistance and both coils read 3.5 ohms. I then started the engine and did the same and back probed the connector on the solenoid and hit the left button and i get 5.68 volts and the right button and i get 5.86 volts. I then switched positions and cleaned the valve stems on the aux hyd and now it works all the time in left side of thumb switch and not in the right side so will this tell me i have a bad stem aux valve. I'm at a lost on what to do. any ideas or help please.