Andy, as I recall, the 300U uses the same power steering setup as the 460U which I own.
One quick check you can do is to make sure the steering wheel raises and lowers on its axis as you turn it from lock to lock. The total displacement isn't a lot, on the order of 1/8" or so, but enough to pick up with a discerning eye.
As I understand the system, the control side of the circuit deals with that axial movement of the steering shaft up and down...which moves a spool off its center. That off-centering sends fluid to the "power" side of the circuit...which is the double-acting piston (a boost cylinder really) that acts on the "helper rack".
I think what I would do is to crack the lines going to the boost cylinder and see if fluid is being sent there (to both sides) by the control side of the circuit. Then you can draw a theoretical line between the control and the power side of the circuit...if my explanation has made those abstractions clear enough.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Identifying Tractor Noises - by Curtis Von Fange. Listening To Your Tractor : Part 3 - In this series we are continuing to learn the fine art of listening to our tractor in hopes of keeping it running longer. One particularly important facet is to hear and identify the particular noises that our
... [Read Article]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
