MTZ 1220.1 Operator'S Manual Download

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MTZ 1220.1/1220.3

Section H. Adjustments

Checking and adjusting axial preload in pivot tapered bearings

Prior to adjusting the axial preload in

the pivot tapered bearings (7) (Fig. H-5a),
peform the following preparatory work:

- clean the PTO of dirt
- install the tractor on an even surface,

brake it and exclude possible movement;

- jack up the front of the tractor

installing supports under the FDA in the
points of jacking;

- unscrew the nuts fastening the wheels

and remove the wheels, observing safety
precautions;

- disconnect the steering rod from the

left and right wheel reduction gears and
remove it from the FDA;

- disconnect the finger fastening the

hydraulic cylinder from the mounting
bracket fixed to the wheel reduction gear;

- using a dynamometer, determine the

force  of  rotation  of  each  wheel  reduction
gear,  first  in  one  and  then  in  the  other
direction.  Apply  force  to  the  wheel  bolts
nearest  to  the  horizontal  reduction  gear
axis.

The axial preload in the bearings must

correspond  to  the  force  of  rotation  of  the
reduction  gear  from  60  to  80  N  applied  to
the  wheel  bolts.  Repeat  the  force  check
three  times  in  each  direction  to  determine
the average value.
With  a  turn  force  of  30  to  50  N,  adjust
preload  in  the  pivot  bearings  proceeding
as follows:

- check the tightening force of the

lower axle bolts (180 to 200 N•m);

- unscrew the four bolts M16 fastening

the upper pivot axle;

- using the extracting bolts, lift the

upper  axle  (4)  (Fig.  H-5a)  and  removing
the  adjusting  shims  (2)  of  the  same
thickness  from  both  sides  of  the  axle
flange, achieve the required preload in the
bearings;

- tighten up the bolts (5) (Fig. H-5a)

fastening  the  axles  to  a  torque  of  180  to
200  N•m,  make  the  tightening  crosswise
with  mandatory  cranking  of  the  wheel
reduction gear;

- re-check the preload in the pivot

bearings by checking the force of turning
the reducer in both directions;

- do the same for the second wheel

reducer.

At a turn force of less than 30 N, before

adjusting  the  preload  in  the  bearings,
unmount  the  bottom  axle  (9)  (Fig.  H-5a)
and  check  the  condition  of  the  lower
bearing.

After adjusting, lubricate the wheel

reducer bearings. Inject the lubricant
through the lubricator in the axles (4), (9).

After adjustment and lubrication of the

pivot connection bearings, install the parts
removed  from  the  FDA  in  the  reverse
order.  Tighten  the  nuts  fastening  the
steering cylinder to a torque of 180 to 200
N•m  and  the  nuts  fastening  the  steering
rod to a torque of 110 to 130 N•m.
Make  subsequent  adjustments  of  the  pivot
bearings every 500 hours.

Checking and adjusting axial play in drive pinion tapered bearings of wheel reducer

Check and adjust axial play in the

drive pinion tapered bearings (14) (Fig. H-
5a)of the gear set as follows:

Use an indicator to check the axial play in

the tapered bearings (1) (Fig. H-5a)
measuring the displacement of the double
joint fork.

The axial play in the tapered bearings

must not exceed 0,05 mm. If necessary,
adjust as follows.

- loosen the fastening of the barrel (3) (Fig. H-
5a).

- using the extracting bolts, move away

the  barrel  (3)  and  removing  the  adjusting
shims 4 (Fig. H-5a) of the same thickness
from  both  sides  of  the  barrel  flange,
achieve  the  required  clearance  of  0.05
mm max.
-  tighten  up  the  bolts  fastening  the  barrel
to  a  torque  of  20  to  25  N•m,  make  the
tightening

crosswise

with

mandatory

cranking of the double joint; To ensure