I think it should fix the problem, the reel lift and dydraflex are run off the same line with a elctrohydralic valve on the right hand side of the head under the removable plastic shield, with a four wire plug on it. One line splits off and goes to the reel lift and the other goes to the hydraflex. I found this out while I was adapting the 620 hydraflex to my 7720, It maybe a little unconventional, but the head works wonderful compared to the 920 head that I had on it.