JD400 steering assist

[down n dirty]

Hi all I recently purchased this jd400 and was wondering if you had to add fluid or if it's meant to pump from the mains to this header tank.
will try and download a manual today to also assist me thanks for your help everybody.

 

[beenthere]

:welcome: to TBN

A bit more information to the question will help. Assume this is the JD 400 Industrial model, but there are several different models it appears from jdparts.

I'd guess that the hydraulics are separate from the engine, if that is what you mean by "pump from the mains".

A bit more exchange of information will help. Your location will help as well, as the reference to "header tank" is confusing.

Am sure someone can chime in to help here. Is this diesel or gas engine, and how about a serial number too. tks

This the model? TractorData.com John Deere 4 industrial tractor dimensions information

 

[Chilliwack Murray]

The header tank above the main pump is filled by the transmission pump. The flow goes to the power steering first with the excess flow filling this reservoir and running through the cooler.

If the power steering is leaking internally and requiring too much flow it won’t keep the reservoir full and eventually cause the main pump to cavitate.

There is quite a bit of info here and Green Tractor Talk if you search JD400 (and skip all the riding mower posts).

There are several variations on the hydraulics depending on the year but they are all closed center systems.

 

[Tx Jim]

Welcome to TBN
Industrial model JD 400 prior to serial # 045200 has open center hyd power assist steering with pump mounted on RH frt of engine. Later models have closed center power assist steering with hyd pressure supplied by frt hyd pump. After SN 045200 a pressure control valve bolted to RH side of trans case very near & rear of hyd filter assure steering gets hyd pressure priority. I agree hyd reservoir is designed to be automatically filled from trans pump by excess oil not utilized by main hyd pump & supplies oil to frt pump when trans pump oil supply to frt pump is lower than supply required.

 

[down n dirty]

Sorry here is a picture of the tractor.

 

[down n dirty]

Hi all I recently purchased this jd400 and was wondering if you had to add fluid or if it's meant to pump from the mains to this header tank.
will try and download a manual today to also assist me thanks for your help everybody.View attachment 643019