Hi, I had this same problem on my 753 machine and it took me three weeks to find the problem. I hope this helps. First connect the hose loop you made (to check flow) onto the aux couplers(just one side if you don't have a guage on the loop) Start the machine and check for flow. (If you don't have a guage and there is flow, oil will start shooting at start up so be ready to turn off engine immediately.) If you have flow on start up without turning on the auxillaries, then go to step two. If you don't then your problem is different from minds and you might want to examine the exact part or parts your mechanic touched on the control valve. Step Two. Look at your control valve and control valve schematics. Find the Aux spool that goes horizontally through the valve body, (not the vertical ones with solenoids on the top) My Aux spool was capped off with covers on either side of the control valve. If yours is the same as minds it will be the third spool counting from the bottom up. Take off the covers and see if the spool valve goes back and forth freely. Minds was stuck in the open position (sticking more towards the front of the machine) which is why I had flow on start up. If it is stuck, get it free, pull it out and clean it. It took a couple of taps with a hammer to free minds. Reinstall, make sure to put springs back in correctly and it should work. Hope this helps. If your not sure, give me a call at 808-645-6145.