john deere 4200 rocker arm lift

[tooter31911]

my 4200 rocker arms wont lift i have changed the hydro oil and replaced the filter and cleaned the screen and replaced the gasket also put in new oil and its full just to the top of the sight glass we also checked the filter in the line going to the rocker arm control valve ,i have checked to see if the stop knob was not turned to the off position and i ran it in and out a few times to make sure just last year i had the dealer replace the whole rocker control valve assembly at the cost of almost 800.00 i cant to this every 14mos wow please anyone can you help with any other thoughts my thank you to all that will answer

 

[kennyd]

Welcome to TBN

By "rocker arms" you mean 3PH (three point hitch) arms? Is there any resistance at all when you move the rockshaft lever? There is several linkages between the lever and the valve inside the housing. You can register at www.jdparts.com to get drawings like I posted below, it's free and there is a quick tutorial linked in my signature if you need help with it.