KENWORTH MEDIUM DUTY STEERING BLEED PROCEDURE

STEERING GEARS ARE HEAVY AND AWKWARD TO HANDLE. IT IS EASY TO GET FINGERS PINCHED OR DROP THE GEAR WHEN HANDLING IT. MAINTAIN A CLEAN WORK AREA.

Sheppard Steering Gears mounted on this type of chassis may experience a momentary bind or catch in the steering when turning the steering wheel quickly to the left. This usually indicates a pocket of air is trapped in the cylinder head end of the steering gear. To remove the air, either vacuum bleed the steering system at the reservoir, or use the following procedure:

1. Secure the vehicle for servicing, wear appropriate personal protective equipment.2. Fill the power steering reservoir with the recommended fluid to the FULL COLD mark on the dipstick or reservoir.3. Remove the cotter pin from the castle nut on the draglink, and the draglink from the pitman arm. Secure the draglink out of the

way.3. Loosen the jam nut on the reservoir hose fitting located on the top of the steering gear 1 full turn, enough to allow the fitting to

rotate. As the steering gear is lowered the fitting will need to rotate to prevent pinching the reservoir hose against the reservoir bracket.

4. Cut one of the zip ties keeping the two reservoir hoses bound together.

5. Secure the steering gear with a strap or bungee around the bumper end (cylinder head) of the gear and the radiator support rod to control how far the gear is able to rotate.

6. LOOSEN the top right mounting bolt. This bolt will be used as the pivot point to allow the gear to rotate.

DO NOT ALLOW THE POWER STEERING FLUID RESERVOIR HOSE TO PINCH AGAINST THE RESERVOIR BRACKET, OR THE STEERING COLUMN TO PINCH ANY WIRING UNDER THE WINDSHIELD WASHER FLUID RESERVOIR AS THE STEERING GEAR IS LOWERED.

7. Remove the remaining 3 mounting bolts and allow the gear to rotate until the steering column is in a fairly straight line (to approximately a 25 degree angle).

8. Start the engine and let it idle. DO NOT RUN THE RESERVOIR DRY!9. Turn the steering wheel all the way to the RIGHT and hold pressure on the steering wheel, keeping the relief plunger

activated. An audible hiss will be heard when the gear is in relief. Hold the gear in relief for 10 seconds.10. Turn the steering wheel all the way to the LEFT (approximately 4.5 steering wheel turns) and hold pressure on the steering

wheel, keeping the relief plunger activated. An audible hiss will be heard when the gear is in relief. Hold the gear in relief for 10 seconds.

11. Repeat this procedure 5 more times.12. Center the steering and shut off the engine.13. Raise the steering gear to its original location and install and tighten all mounting bolts to Kenworth’s specifications.14. Ensure the hose fitting for the reservoir hose is in the correct position and tighten the jam nut.15. Install a new zip tie to bind the two reservoir hoses together.16. Connect the draglink and torque the castle nut to the manufacturer’s specification. Install the cotter pin.17. Reset the automatic relief plungers as follows:

1A relief plunger is placed in each end of all Sheppard steering gears (with the exception of slave gears) to unload steering system pressure prior to the axle stops contacting the axle. One is located in a small hole in the bearing cap cover next to the input shaft. The other plunger is on the opposite end of the steering gear and may be in a hole in the cover, or in the hole in the end of a boss sticking out from the cover. The hole may be covered with a plastic plug or cap. Both the auto and manual plungers have a slotted head for a screwdriver and look alike. They both will be located either on the engine side or the tire side of the centerline of the steering gear.

BEARING CAP PLUNGER CYLINDER HEAD PLUNGER

FAILURE TO SET OR ADJUST THE RELIEF PLUNGERS MAY RESULT IN DAMAGE TO THE STEERING SYSTEM AND CHASSIS. PLUNGERS MUST BE SET OR ADJUSTED ON ALL REPLACEMENT

STEERING GEARS!

18. AUTO plungers are RESET by tapping them in with a 1/4" punch and small hammer until you feel the plunger bottom out in the bore. Be careful not to score the plunger bore. Scoring the bore will cause a leak which cannot be repaired. DO NOT USE EXCESSIVE FORCE TO DRIVE THE PLUNGERS IN-IT WILL DAMAGE THE BEARING CAP AND ROTARY VALVE. The head of the plunger will be 1”-1 1/8” deep in the plunger hole when it is bottomed out.

19. Raise the steer tires off the ground and SET the autoplungers by turning the steering wheels from side to side until the axle stops contact the axle. The stops MUST contact the axle.

20. Sit the vehicle back on the ground. Start the engine and turn the steering wheel completely from stop to stop several times and check for any signs of air remaining in the system. If air is still present, repeat the bleed procedure.

If you have questions at any time, refer to the Sheppard website www.rhsheppard.com/service , or contact our Field Service Hotline at 1-800-274-7437.