JD 318,322,332,420,430 Steering Control Valve Leak, Rebuild Tips Tricks

…Continued Pt 3
Another close up pic of the crowfoot wrench tightening a hydro line. In my experience, this is far superior to using a std wrench.

Now with all of the lines attached, it’s time to install the last two of four nuts to retain the valve body in place. If you didn’t first remove the ignition switch before removing the valve, you’ll want to kick yourself afterwards. While disassembling, I removed it after removing the right tower panel + the drive lever plate/drive speed plate. The drive plate slides up (gently) out of the dash once disconnected.


For those who don’t like tearing up chrome, before removing the ignition switch, I wrapped its outer chrome ring (about a 1/4” edge) twice with the colored vinyl tape – to avoid ruining the chrome finish as I rotate it counterclockwise with groovelock pliers.

In my next pic – Below and to the right of the ignition hole is the back left valve bolt with a glistening/shiny nut above the valve mounting plate. Much easier to reach this nut with the drive speed plate and the ignition out of the way.


In this same area is the drive dampener / absorber this model 430 has (some have said in posts you must remove it to deal with the valve). From experience, it’s not any easier to remove the valve with the dampener out. I had no problems removing the valve or reinstalling it with the dampener / absorber and surrounding arms intact (shown in next pic).


One of the remaining pain points is the back right valve body retaining nut. No wrench goes in easily or allows any speed turning it. I used a wrench to break it loose during disassembly. Then loosened it with a ratchet+beveled extension+universal joint socket adapter. I also used this ratchet combo to tighten it. It goes on fast!




I chose not to fully reassemble the tractor before testing the valve for leaks. I had the battery on the floor and used short, quality jumper cables to bridge the battery to the tractor’s + – cable ends.

Key point: Do NOT be tempted to turn the wheel L or R – the valve is dry and needs to be recharged with hydro fluid!!

The manuals discuss an air bleeding method with multiple steps. Don’t go that path! There’s no fluid in the valve yet, so air bleeding isn’t necessary at this time.

Start the engine at 1/4 throttle. Check the valve and hydro lines for any signs of leaks. Advance throttle to half. Check for leaks. To recharge the valve with fluid, take hold of the hydro lever you’d use to raise/lower the deck/3point hitch, then move it back and forth (full cycle each direction). That motion shoves fluid into the valve + through and out of it quickly. I cycled the lever 20+ times before I ever attempted to turn the steering wheel. Check for leaks again.

Out of an abundance of caution with this used valve, before disassembly I had drained the transmission, replaced the hydro fluid and filter.
Confident it had fluid, I proceeded to test turning the steering wheel. It worked great, moved easily. I then went into reassembly mode: Firewall, R Side Tower, Battery Pan + Battery, Seat pan + Seat, Torqued Steering Wheel retaining nut to the JD ft lbs spec.

I took it out for a spin and went from easy to turn over to hardly any power steering assist! It became tight, sluggish. I drove it for about five minutes and it never improved. I reasoned the flush and fill that I did might have allowed too much air in the system. I left the tractor idling for twenty minutes in the driveway. I returned to find out no lengthy air bleed process was needed / it self-purges.

I’ve since used it mowing 1.5 acres for many engine hours and in multiple weeks of 90 degree temps. I’ve also used it all fall for leaf duty on my property and now snow removal. I’m happy to report no problems whatsoever / this upper-end-only / lite rebuild method works well, with longevity.

Going backwards to disassembly.
Key Point: when loosening hydro lines at the valve ports, there are multiple lines to follow back to the opposite end and loosen there also to allow the valve body to slide past the lines. I’ll explain with pics below.

On the top of the left frame member are two hydro lines bound to the frame for the steering piston. If you will loosen these two retainer bolts from the frame, you will save yourself a lot of grief getting the valve body out and back in! No need to loosen lines at the steering piston/cylinder end, just these retainers!


So too with this line shown below, if it’s not loosened let the life pain begin when it’s time to remove or reinstall the valve body.


At the hydro pump, this line below has to be loosened. Set some paper towel beneath it as the fluid will flow if the system wasn’t first drained.
In front of fuel tank-


Under the left side behind the muffler-


Key Point: Looking back to the beginning – what did I remove during disassembly?

Seat and Seat Pan, Battery and Battery Pan, Right tower side panel, Firewall bolts at bottom – one at right side & one at left side, plus firewall bolts at top right holding coolant support bracket and battery cables. If you remove these, it frees the firewall panel to tilt up to top left (away from you standing at right side of 430) and allows the valve to slide in/out at bottom right (with some wiggling and freeing the steering shaft top from the wiring beneath the dash, go slow, pay attention, it will come out with finesse.

What else? A cross member that ties to right and left tower side panels and holds the fuse box for newer series 430s – it has four bolts on the outside (2 each R, L tower panels) and one on crossmember face near the drive speed plate.

As mentioned: 1. I also removed the drive speed plate and the ignition module. 2. In Round 1 rebuild I did replace the drive speed dampener/absorber as it was an original and it’s an ideal time to replace it.

Key Point: before you take out the valve body or disconnect lines-either degrease and pressure wash (ideal) or hand clean the valve body, the hydro lines, the whole area around the valve. Blow out the area with compressed air. Get all of the dust and crud you can out of the area beforehand.

Leave a Comment