350 utility power one way power steering

[Paul 300 U]

I purchased 350 almost a year ago,
primarily for the loader. Starts great
good oil pressure trans,ckutch,pto, t/a
all work. Big problem was power steering
only worked in one direction. Turns
right ok (I think it was right??) but
turning left is very difficult.
I tore down the steering assembly.
Replaced damaged needle bearings, sector
pin and seals. All else appeared to be
good. The only part I did not disassemble
was the steering cylinder with the
piston. I also had a ram rebuilt and 2
hoses for the loader
When I reassembled the loader worked
great, but steering still had same issues
plus i created leaks above and below the
adapter valve. (Last pic)
I've purchased new seals for the adapter
area as well as the steering cylinder
based on advice the problem could be
created by bad seals leaking in the
cylinder interfering with the operation
of the Adapter valve.
My primary question for this post is that
in rereading the manual to see what I
missed, the Assembly and Adjustments
(8#35) says the steering wheel should
move up and down about .10 of an inch
when turned completely from one direction
to another. Mine does not appear to be
moving up and down which has me concerned
that the steering valve is not able to
function correctly. I'm wondering
whether I did an adjustment wrong. It
seems there are 2 key adjustments. One
has to do with an eccentric screw in the
assembly and the 2nd is the locking nut
at the top of the steering column. I've
attached pics and the instructions from
the manual. I'm hoping someone here can
add clarity to exactly how to make these
adjustments.
I'm also open on getting feedback on
other ideas on why this tractor only
turns one way.
Thanks for the help! Paul

 

[Janicholson]

If it is not moving up and down the control valve will have no input motion to direct pressure to one side of the cylinder, or the other. Jim

 

[S.Hess]

So I have recently become the owner of a 350u with a pippin loader and backhoe myself. The power steering on my machine leaks everywhere so I have been searching the internet all over for solutions to it. I found on another site a fellow having the exact same issue as you are. One of the old timers said that part of the steering system has a high spot in it that causes air to get trapped in there when the system has a.leak and runs low or the guild is drained and replaced. The old timer said to take a air hose pressured to 10 psi to pressurize the system enough to move the hydraulic fluid through the high spot but a low enough pressure as not to damage the system. For the life of me I can't remember where I seen this information, but as I am going to have to get into mine in the near future it was a bit of info that I decided to keep in mind.

 

[S.Hess]

I hate when I have to walk back what I say, but I searched for the post that I was looking for and after about 2 hours finally found it. Turns out the post that I found was talking about pump cavitation between the reservoir and the pump, since you have ps in one direction I do not feel this will be of any use to you.

 

[Paul 300 U]

Thanks Jim. Would what you are describing prevent the steering from turning in one direction?
If so do you have any suggestions on how to correct? My skill level aside...
Would you figure it is a parts problem or an adjustment problem?
I have some confusion in part because the Reassembly Instructions for power steering in the Repair Manual tell you to refer to the Adjustments section which is found in the manual steering section. While I'm sure the manual steering assembly and the power steering assembly are very similar, the position of some of the adjustment screws appears different. Also there are parts differences, (ball bearings,for the 300 vs needle bearings for the 350. See pics of 350 disassembled that may spark ideas). I don't know if the parts differences are creating other issues that I'm missing.
Thanks for the help. Paul

 

[Paul 300 U]

Hello all,
I'm not sure of the etiquette here but I did post additional info and pics under Janicholson. Probably info overload!
I'm letting you all know to look there because I don't want to discourage feedback from others or overburden Jim. Thanks for the assistance. Paul

 

[Janicholson]

Inside the control valving (second picture and third) is where the issue is likely to be. The reason the shaft is supposed to move in and out when steering is that a centering spring set keeps fluid flowing through the valve to the reservoir when not turning. When turning the steering wheel motion is not direct to the worm, its first rotation force compresses the spring downward creating flow to one side of the piston. releasing it from the other. When turning the other way the other spring compresses sending oil to the opposite side of the piston. If there is rust or a piece of Oring in the valve, it can stop the in/out motion. The steering wheel should move about an inch on the rim when the tractor is shut off in either direction, not including wear or looseness. Jim

 

[Paul 300 U]

Not a problem ar all. I appreciate you digging into the memory banks for a possible solution. Paul

 

[Paul 300 U]

Thanks. I washed all those parts in parts wash. Looks like I'm going to have to open it again to see what i missed. Some of the plungers were less responsive then others. I'm wondering if that could be the issue. If my memory serves me it seemed to be more about the springs versus the plunger itself. Thanks again. Paul