Toro 3505D Lawn Mower User Manual


 
Groundsmaster 3505--D Hydraulic SystemPage 4 -- 49
Procedure for Steering Control Valve
Test:
1. Make sure hydraulic oil is at normal operating tem-
perature.
2. Perform the Lift and Steering Control Valve Relief
Pressure and Gear Pump (P2) Flow tests to make sure
that pump and relief valve are functioning correctly.
NOTE: This steering test procedure will be affected by
incorrect rear tire pressure, binding in the hydraulic
steering cylinder, extra weight on the vehicle and/or
binding of the steering fork assembly. Make sure that
these items are checked before proceeding with any hy-
draulic testing procedure.
3. Drive machine slowly in a figure eight on a flat level
surface.
A. There should be no shaking or vibration in the
steering wheel or rear wheel.
B. Steering wheel movements should be followed
immediately by a corresponding rear wheel move-
ment without the s teering wheel continuing to turn.
4. Stop unit with the engine running. Turn steering
wheel with small quick movements in both directions.
Let go of the steering wheel after each movement.
A. The steering control valve should respond to
each steering wheel movement.
B. Whensteering wheelis released,steering control
should return to the neutral position with no addition-
al turning.
5. If either of these performance tests indicate a steer-
ing problem, determine if the steering cylinder is faulty
using the following procedure.
A. Park machine on a level surface with the cutting
units loweredand off.Make sure engine isoff andthe
parking brake is engaged.
B. Turn the steering wheel all the way to the left
(counterclockwise) so the steering cylinder rod is ful-
ly extended.
C. Read Precautions for Hydraulic Testing.
D. Remove hydraulic hose from the 90
o
fitting on the
rod end of the steering cylinder. Plug the end of the
hose.
E. With the engine off, continue turning the steering
wheel to the left (counterclockwise) with the steering
cylinder fully extended. Observe the open fitting on
the steering cylinder as the wheel is turned. If oil
comes out of the fitting while turning the steering
wheel to the left, the steering cylinder has internal
leakage and must be repaired or replaced.
F. Remove plug from the hydraulic hose. Recon-
nect hose to the steering cylinder fitting.
6. If steering problem exists and steering cylinder
tested acceptably,steering controlrequires service (see
Steering Control Valve and Steering C ontrol Valve Ser-
vice in the Service and Repairs section).
Hydraulic
System