JLG 40H Telescope in,steering and basket rotate/tilt stop working

This is a pre 1995 unit with ford engine and standard controls as shown on page 3-34 and 3-35

2 years ago I had the same problem and replaced the inner parts and springs to the Main relief valve. pg 2-46 and 2-47
it still did no work with the new parts but then I cleaned out the hole and then all of a sudden it started to work. I thought there must have been a piece of dirt in the bottom.



Now it is doing it again I installed a pressure gauge on the control valve assembly. The symptoms...

JLG 40H Telescope in,steering and basket rotate/tilt stop working

JLG 40H Telescope in,steering and basket rotate/tilt stop working