4430 Trans pump

[Eastfork]

About a year ago I had the trans pump replaced on my 4430. The tractor hydraulics chattered bad and with the help from you guys and the JD dealer it was perfect afterwards (just a half second delay when I pulled the lever). They were surprised it even worked at all as bad as it looked. Throughout last summer it started getting worse again and now its as bad as it was before. I changed the Hyd filter a few months ago and didn't help. I just checked the pump screen yesterday and its clean. I did notice that the oil has lots of tiny bubbles (ran for about an hour beforehand) like either oil starvation or cavitation. They sad the front pump tested out fine at the time of repair with good flow and pressure. It seems the dealer is avoiding me when I ask about it. Could something have come apart on the inside? I was thinking of trying to run it a gallon over full to see it makes a difference.

 

[tim s]

I'm thinking that you have a Quad Range trans.,,and a gallon over full will not help you with this issue,,You could have a clutch oil leak,,and yes the front pump may be going bad too,,You should start out by testing you clutch oil circuits,down in the left side at the clutch operating housing, the ports are marked,, get a 300 lb gauge and do what you need to do to screw a 2ft hose into one of these ports at a time, clutch oil PTO, and PTO brake, see and write down the readings with the clutch up/down,PTO on/off,,,in high/low..then plumb a 5000psi gauge into one side of the SCV, engage the lever and see what you have there,,check back with us and we can help decide what you should do next..

 

[RogerinIowa]

Lots of tiny bubbles would indicate an air leak on the suction side of a pump, but the front pump has some pressure on the suction side.
Any sign of an oil leak on the line from trans pump to the front pump? That would indicate a possible air leak when the front pump is
operating.

Other wise it would seem the leak is on the suction side of the trans pump. Sorry I do not have any experience with the trans pump
configuration.

 

[Eastfork]

Thanks Tim. I'll round up some gauges and a service manual hopefully in a few weeks. I'll let you know what I get for readings.

 

[Eastfork]

Hey Tim. I finally checked pressures and got 180psi on the test ports and 2250 on the outlet. None of the test ports changed with doing different functions.