[mishnick]

If the rams are jerking then that suggests that the S3 valve is not opening when you hit the up button. But you said that left and right angle works right? This could be a controller problem... It could be as simple as the idea that when you press the up button that the only thing that happens is the motor is engaged. This would make the pump push fluid through the S3 valve right into the left angle ram and through the crossover relief to the right ram and then dead end at the closed S2 valve. What I suggest is to put a test light on the S3 coil and get someone to push the up button. The light should turn on. Then you could (carful not to get squished behind the blade) get your helper to push the left angle button. S3 should light up for both those actions. I suspect it will only light up for left angle. This explains your symptoms perfectly. You have lots of pressure, it turns left and right, goes down but wont go up. Try a different controller my friend. You could also try just hot wiring the S3 valve with a jumper cable and then hit the up button. This will ensure the S3 is powered and I bet it will go up. Let us know how you make out...

 

[mark-lehmer]

I went to the westen dealer today and bought all 3 vavles ,installed them , no more jerking . it still won't lift all the way up.I did unplug all the coils then run jumpers, all seems well. I did unhook the lift chain and wraped it around the lift arm two inches back from the end. lifted good and plenty high enough.
I will seach at work to see if I can find another gauge, to dbl check the psi
I see they offer 2 diffrent length lift arms, mine is12 inches long. maybe it takes a shorter one ?