H1520 Power Steering project...

James Eric · Feb 18, 2018

I purchased a power steering unit online last year because it was way under priced and I was the only bidder. This is my second power steering modification on a tractor. The first one is on my Case 444 garden tractor. The power steering valve is a 5 port unit off of a JD 318. It is a Hydraguide HGF valve. I checked with Parker/Ross and this valve is rated to handle the full 1850 psi from the Hydro unit. The H1502 still gets the full 1850 psi and 3 gpm flow from the Hydro. The 3 gpm flow is not as responsive as my Case 444 with 5 gpm but it beats pulling on the wheel with 500 pounds in the loader. I have a loader to add later this spring.

-I tapped into the output of the hydro just under the seat for power. The power steering is first in the circuit giving it top priority.
-The AUX output on the valve then goes to a 2 spool control valve mounted on the fender with power beyond.
-The power beyond from the 2 spool control valve loops back to the 3 point.

All of the steel used was collected in my travels or from a local fabrication shop scrap bin. The cylinder mount is 3/8"x2" angle iron. The JD steering wheel is a little smaller than the original. Also, it is 3" taller which I personally like better. Most of the hoses and fittings came from Surplus Center. The cylinder stroke is 3-1/2" just like original. It could used spacers on a 4" stroke cylinder but I found a this 3-1/2" cylinder at Surplus Center. I cut the rod and attached a swivel with a spring pin. The power steering mount is made with scrap 3/8" steel plate and bar cut to fit as needed.

FYI - The AUX port is the "POWER BEYOND" and the "RETURN" to the tank. The port marked "T" only operates when the power steering is actively turning the wheels. Therefore both the AUX and the "T" port must both be plumbed to the tank at all times or you can lockup on blow your system.

Thanks for reading,

James

PILOON · Feb 18, 2018

On my 'to do list' as well.
I bought an orbital valve on EBay ($40.00 ish) and have now a modified cylinder plus the ball ends now attached to the cylinder.
Plenty of hydraulic hose on hand.
It remains to make the frame mount bracket and a 'pedestal' like affair to mount the orbital valve.
One problem is my manual steering wheel is spline mount ant the splines do not match up with the orbital valve. OK, I could always jamb the wheel on but then I be stuck.
Would much prefer to locate a wheel with proper splines and if possible a tad smaller.

It is one of my many 'ongoing projects'.
My excuse is that I had some health issues (now resolved).

Kernopelli · Feb 19, 2018

Excellent job, very clean fab work and install! Take it from me, you'll really appreciate it with a loader.

Just like Piloon, I too have assembled nearly all the components for a PS upgrade and have had them for several years. My excuse was always that I was too busy ( now resolved becausse I retired 6 months ago) but it is still on my "ongoing projects" list too. Guess I could be out in the garage working on it right now instead of drinking coffee and playing on the computer.