greenmachine59
New User
I've been chasing a problem on my 4620 hydraulic system and not getting anywhere with it. The tractor works almost perfect in winter time on feeder wagon when oil is cold. Most people wouldn't even notice an issue. But if I put it on my haygrinder and she warms up the hydraulics chatter terrible and the belt conveyor will speed and slow down, I even had it once quit totally and had to move hydraulic valve back and forth few times to get going. Now that it is warmer it is chattering all the time. Yes it is always full of oil. Gave it a full service on oil, filters screen. The screen was totally clear. Hydraulic pressure has been at 2400 psi no problem but if I start a second valve with hose routed within on the valve just so it flows my pressure drops to 500 psi and the priority valve is the culpert of the chatter. I checked the trans pump, plenty of pressure filled 5 gallon bucket in 25 seconds, checked at line going into pump, same, I thought well, the pump gives me pressure but no flow, possible problem inside, I replace the main hydraulic pump, problem not solved, I've inspected through the plug on back of rearend for leaks and have seen nothing with light. Steering and brakes all work fine, If I am flowing with the scv valve the pto will grind as it doesn't have enough pressure for the clutch. I obviously have a leak somewhere and am chasing but not much luck in finding, right now I have the priority valve off to inspect but it all looks good, there is three shim washers in it with the spring. I have felt lines but not really noticing heat but havn't really worked the tractor since in shop either. Also this tractor is a power shift