Under your left leg is a black knob. It has numbers on it,, 1, 1.5 2 etc and "top". There is a black arrow on the floorpan right above the knob. Raise the 3ph all the way to the top. Turn the knob to align "top" with the arrow. When you let the 3ph down , the mower deck should stay up. If the deck is adjusted too low, it may not catch the latch that holds it up. Look at the knob from the bottom while turning it and you can figure out how it works.
