ADJUSTMENT cont'd

TM 55-1740-200-14

o. Release the cab steering lever (1) and place cam

so that pitman arm contacts stop screws (15) to leave 1/8

(35) in position as shown in detail C. With the cab lever,

inch clearance between the wheel spindle arm and the

free adjust nut (19) until clearance between cam (35)

wheel stub.

lower ramp and roller (30) is approximately 0.010 inch.

p. Turn cam (35) back and forth between the two

positions shown in details B and C and observe the action

of spring (25). As the roller (30) comes off the upper

If pitman arm stop screws (15) are not

cam ramp and onto the lower ramp, spring (25) should

adjusted to stop wheel turn prior to contact

extend to return roller (30) to the 0.010 inch clearance

between wheel spindle arm and wheel stub,

setting. Failure of the spring to extend indicates binding

the spindle arm will become fatigued and

of lever (36), caused by insufficient lubricant or nut (37)

cause it to break thereby loosing front wheel

being too tight, or defective valve (22).

steering control.

q. Reconnect ball joint (33) but do not install nut

i. With engine off, place jack under tractor and raise

(34). Start the tractor engine and verify that the cam (35)

until both rear wheels are clear.

automatically returns to the position shown in detail A

and that roller (30) stops halfway between the upper and

j. Disconnect ball joint (33) by removing nut (34) on

lower ramps on the cam. Check the rear wheels and verify

lower end of cam lever (35).

straight-ahead position. If the rear wheels are not in

straight-ahead position, shut the engine OFF and lengthen

k. Measure between the centerline of the cam pivot

or shorten linkage. Remove ball joint (33), loosen nut

point and the centerline of the link connecting hole. If

(32) and adjust ball joint (33) on rod (31) as required.

distance exceeds 7-1/4 inches remove cam (35), weld link

Reconnect ball joint, start engine and repeat check.

connecting hole closed, and redrill to 7-1/4 inches.

r. When step q is completed, push the cab rear steering

NOTE

lever (1) to the extreme left and carefully observe the

cam (35) as it approaches the position shown in detail D.

On early model tractors this dimension was 7

As the roller (30) comes to the end of the curved upper

1/2 1/8 inches.

ramp of the cam it moves onto the straight beveled part

of the cam, which forces the spring (25) to compress

1. With cam lever (35) in position as shown in detail

approximately 1/16 inch. This is the automatic valve

A, measure the distance between adapter (28) and valve

shutoff in this direction of turn. Failure of the cam to do

(22). Distance should be 1/2 inch. Adjust distance by

this indicates one or more of the following problems:

loosening clamp nut (27) until clamp (26) is free, placing

a 9/16 open end wrench on the connecting link wrench

(1) The distance between the cam pivot hole and

flat and turning upward to lengthen or downward to

the linkage hole is greater than the 7-1/4 inches.

shorten.

(2) This section of cam (35) is badly worn and cam

should be replaced,

NOTE

(3) The roller (30) is badly worn and should be

The wrench used should not be over 3/16

replaced.

inch thick.

m. Turn nut (20) downward and nut (19) upward

s. Push the cab rear steering lever (1) to the extreme

until springs (39 and 40) are loose and under no

right and observe the cam as it approaches the position

compression.

shown in detail E. As the roller (30) comes to the end of

the curved portion of the lower ramp, it moves off onto

n. Place cam (35) in position shown in detail B, place

cab rear steering lever (1) in extreme left position and

the straight beveled portion of the cam, allowing spring

check the clearance between cam (35) upper ramp and

(25) to extend by approximately 1/16 inch, which is the

roller (30). With cam (35) and steering lever (1) held in

automatic valve cut-off in this direction of turn. Failure

these positions, adjust nut (20) until clearance is

of spring to extend indicates one of the following

approximately 0.010 inch.

troubles:

4-6