4320 hydraulic problem

Tim Heuiser · New User Joined: 03 Jun 2009 Posts: 2 Report to Moderator

I am still fighting my 4320. I quickly loose power steering, brakes and three point hitch when I depress the clutch. The front pump and the transmission pumps are both new. Anyone have an idea where the leak could be? The PTO seems to work fine.

Bob · Posted: Tue Jun 23, 2009 12:02 pm Post subject: Re: 4320 hydraulic problem

You likely have a "high pressure leak to sump" keeping the main pump "in stroke", quickly using up the oil stored in the oil cooler when the clutch is depressed and the transmission pump stops..

Starting with the tractor COLD, the component leaking will heat up faster than the rest of the system.

Could be steering valve, 3-point hitch valve (if so equipped) or an SCV.

tim s · Posted: Tue Jun 23, 2009 12:05 pm Post subject: Re: 4320 hydraulic problem

I have had this problem many times and "most" of the time it's the PTO valve under the dash area, there is a return port to let the oil return when the pto brake is released or when the clutch piston is released ,,it seems that the valve body gets worn and lets pressure continue to bypass to this return, and when this happens you run out of trans oil supply quickly, Deere used to offer a complete valve for about $400, but it's not offered complete anymore, about the only way to isolate it is to make a plate to bolt on in it's place or maybe tap out the persure port to maybe 1/8 pipe and plug it, I have thought about this but not done it yet. And of course it could be any one of the other components leaking back to sump, Isolate them one at a time till you find it is the best to do.

matthies · Guest Report to Moderator

Do as Bob advised, and don't forget about the pto valve under the dash. Have seen quite a few leaking internally lately.