Troy-Bilt Horse Tiller Technical Manual - Page 20

PTO

HORSE

MODEL

TECHNICAL

MANUAL

Page

5.4

4/90

SECTION

5:

PTO

Power

Unit

Transmission

cannot

do

this

with

your

fingers,

insert

a

long

bar

in

through

the

rear

of

the

housing

to

tap

the

bear-

ing

cup

out.

Be

careful

to

not

damage

the

inside

of

the

housing

or

the

(internal)

snap

ring

(21).

16.

The

(internal)

snap

ring

(21)

can

be

removed

(if

necessary)

by

reaching

through

the

rear

of

the

transmission

with

snap

ring

pliers.

17.

The

front

and

rear

drive

shaft

bearings

(19)

are

pressed

-on

and

can

be

removed

(if

necessary)

with

an

arbor

press

and

a

bearing

puller

attachment.

After

removing

the

bearings,

remove

the

shoulder

washers

(22),

if

so

equipped.

Inspection

These

instructions

describe

how

to

inspect

vital

parts

on

the

PTO

power

unit

drive

shaft.

In

addition

to

inspecting

the

parts

you

have

removed,

you

should

also

inspect

any

replacement

parts

you

will

use.

Note:

Thoroughly

degrease

and

clean

all

parts

before

inspection.

Drive

Shaft

—

1.

The

drive

shaft

should

not

be

scored,

pitted,

or

corroded

where

the

oil

seals

are

located.

•

If

the

shaft

is

scored

around

the

oil

seal

areas,

discard

the

drive

shaft.

•

If

the

shaft

is

pitted

around

the

oil

seat

areas

you

may

be

able

to

relocate

the

oil

seals

to

a

smooth

area.

•

If

the

shaft

is

corroded

around

the

oil

seal

areas,

try

using

fine

(400

grit)

emery

cloth

to

clean

the

area.

2.

Before

installing

the

drive

shaft

you

should

use

400

grit

emery

cloth

to

polish

the

shaft

up

to

and

including

the

keyways.

This

will

prevent

cutting

of

the

oil

seals

when

they

are

installed.

Wear

Area

Figure

5-3:

Inspecting

the

Worm

on

the

PTO

Power

Unit

Drive

Shaft.

3.

The

snap

ring

groove

should

be

just

wide

enough

to

fit

the

snap

ring.

If

the

groove

has

expanded,

discard

the

drive

shaft.

Also,

examine

the

edges

of

the

snap

ring

groove.

If

the

rear

-facing

edge

on

the

groove

is

rounded

off,

you

should

not

reuse

the

drive

shaft

as

this

edge

bears

the

force

of

the

snap

ring.

You

can

reuse

the

drive

shaft

if

only

the

front

-

facing

edge

is

rounded

off.

Worm

—

The

threads

on

the

worm

should

not

be

excessively

worn.

Since

only

the

middle

of

the

worm

is

in

contact

with

the

bronze

worm

gear

on

the

pinion

shaft

assembly,

you

can

compare

the

outside

threads

of

the

worm

with

the

mid-

dle

threads.

If

the

width

of

the

threads

in

the

middle

is

half

or

less

than

the

width

of

the

threads

at

the

ends

of

the

worm,

discard

the

drive

shaft.

See

Figure

5-3.

Also,

inspect

the

worm

for

heat

damage.

If

the

worm

has

a

bluish

color

then

proper

lubrication

has

not

been

maintained;

discard

the

drive

shaft.

Bearings

-

If

the

bearing

has

a

bluish

color

then

proper

lubrica-

tion

has

not

been

maintained;

dis-

card

the

bearing

and

bearing

cup.

Also,

if

the

bearing

or

its

cup

is

scored

or

excessively

worn,

dirt

may

have

gotten

inside

to

the

shaft.

If

the

cup

is

scored

or

excessively

worn,

discard

the

bearing

and

bearing

cup.

Inspect

for

chipped

or

broken

roller

bearings,

and

inspect

the

bearing

cage

for

damage.

Note:

Bearings

and

bearing

cups

must

be

replaced

in

pairs.

Do

not

mix

old

and

new

bearings

and

bearing

cups.

Installation

Use

Figure

5-2

as

a

reference

for

part

locations

in

these

instructions.

1.

Make

sure

the

pinion

shaft

assembly

is

in

place

and

correctly

installed.

See

the

pinion

shaft

installation

instructions

in

this

section.

2.

Install

the

(internal)

snap

ring

(21)

that

retains

the

rear

bearing

cup

in

the

rear

of

the

housing.

3.

Install

the

rear

bearing

cup

(20)

with

the

tapered

end

facing

forward

to

receive

the

bearing,

by

inserting

it

in

through

the

top

of

the

housing

and

setting

it

toward

the

rear.

If

necessary,

use

an

old

drive

shaft

inserted

into

the

front

of

the

housing

to

seat

the

bearing

cup.

4.

Using

#30

weight

oil,

lightly

lubricate

both

bearings

on

the

drive

shaft.

Note:

Follow

this

procedure

to

install

a

new

bearing

on

the

drive

shaft:

a.

Place

a

shoulder

washer

(22)

on

the

front

and

rear

of

the

drive

shaft.

If

reinstalling

a

shaft

that

did

not

have

shoulder

washers,

do

not

install

them.

b.

Using

an

arbor

press,

install

the

bearings

until

they

stop

on

the

shaft.

Use

a

bearing

cup

as

a

base

to

hold

the

bearing

as

you

are

pressing

it

on.

20

Troy-Bilt Horse Tiller Technical Manual - Page 20

Inspection, Installation

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