SANY Crawler Hydraulic Excavator SY195C9, SY205C9, SY215C9, SY225C9. Service Manual

8-95

Disassembly and Assembly

8.27.1 Disassembly

1. Drain the oil and remove the tubing.

2. Fix the cylinder.

●

Fix the cylinder in a vertical or level
manner. A vertically fixed cylinder can
be disassembled and assembled eas-
ily.

●

The pin bore in the head end can be
used for fixing of the cylinder. The pin
roll can prevent the cylinder from turn-
ing.

●

Remove the tubing in case of tubing in-
terference while

xing the cylinder.

3. Removal of cylinder head

●

Unscrew the bolts with Allen Wrench.

●

Using an extension rod, as shown in
the illustration on the right, will make
the work easy.

ZX215-1006164

Fix the cylinder

ZX215-1006165

Approx 1.5m

8-96

Disassembly and Assembly

4. Pulling out the piston rod

●

Be sure to have removed the tubing
cover.

●

Prepare a suitable container to collect
oil coming out of the oil port.

●

After pulling out the piston rod to its
limit, slowly loosen the cylinder head
and pull it out.

●

Remove the piston rod (1) with the
cylinder head (2) and place them on a
wooden sleeper.

5. Fixing the piston rod

●

Use pin bore on the rod end or the

part of the ear to prevent turning of the
piston rod.

ZX215-1006166

Sleeper

ZX215-1006167

Fixing

8-97

Disassembly and Assembly

7. Removal of piston assembly

●

Remove in turn the piston (7), buffer
sleeve (6) and cylinder head (2).

6. Remove of the piston nut (5)

1) Remove the fixing screw (3) from the

piston nut (5).

NOTE: Around the fixing screw there
are two points that have been punched
against loosening. After removing the
riveted part with a hand drill, loosen
and remove the

xing screw (3).

2) Remove the steel ball (4).

3) Remove the piston nut (5).

NOTE: The piston nut (5) is very tight.
To loosen the piston nut (5), prepare
a hydraulic jack or a spanner powered
by hydraulic cylinder. An extension rod
should be ready when removing the
piston nut (5) manually.

ZX215-1006168

Drill bit

ZX215-1006169

Hydraulic jack

Hydraulic cylinder

ZX215-1006170

8-98

Disassembly and Assembly

8. Removal of the buffer sleeve (8) on the

bottom end

1) Remove

rst the piston nut (5).

2) Use a tool like rubber hammer to tap

the piston nut (5) slightly for removal
while keeping the piston rod and the
buffer sleeve (8) intact. Remove the
elastic ring (9).

3) Slide the buffer sleeve (8) toward the

piston threads in order to remove the
two-piece stopper ring.

4) Remove the buffer sleeve (8).

5) There is an opening in the buffer seal

(10). Take advantage of this opening to
remove the buffer seal (10).

9. Removal of piston seal

1) The slide ring (12) and the guard

ring (13) can be simply removed with
hands.

2) The seal (14) can be removed with a

hammer and a

at-head screwdriver.

3) Remove the O-ring seal (15) with a pry

bar.

NOTE: The removed seals should not
be reused.

10. Removal of buffer ring (16)

NOTE: The buffer ring (16) is installed
in the inner groove in the cylinder head.
Use a tool with sharp end to pry it out and
remove it with a scraper.

ZX215-1006171

Thread

Piston rod

one gap

(2 pcs)

ZX215-1006172

Bench clamp

Piston

Screwdriver

ZX215-1006173

8-99

Disassembly and Assembly

11. Removal of the U-ring (17) and the dust

ring (18)

1) Remove the U-ring (17) with a tool such

as screwdriver.

2) Pierce a tool (such as a screwdriver)

into the dust ring (18) and hammer the
screwdriver to remove the dust ring
(18).

NOTE: The removed seals should not
be reused.

12. Removal of bushing (19)

1) Remove the elastic ring (20) from the

cylinder head (2) with a screwdriver.

2) Push the bushing (19) out with the help

of clamps and press.

13. Removal of bushing (21)

1) Remove the dust ring (22) on the side

of cylinder barrel and piston rod with a
tool such as screwdriver.

2) Remove the bushing (21) with the help

of a suitable cushion block.

ZX215-1006174

Press

Cushion

Support

8-100

Disassembly and Assembly

8.27.2 Assembly

1. Installation of bushing (21)

1) Use a mounting tool to press the bush-

ing (21) into the bushing (lubricated
with hydraulic oil) on the side of piston
rod and cylinder barrel.

2) Install the dust ring (22) with the help of

a suitable cushion block.

2. Assembly of cylinder head (2)

1) Use the press to push in the bushing

(19).

NOTE: Apply hydraulic oil to the inside
of cylinder head in advance. Make
sure that the bushing (19) pushed in is
free from a raised shoulder.

2) Use the press to push in dust ring (18).

3) Install the guard ring and the U-ring (17)

sequentially in the U-groove.

NOTE:

●

Install the U-ring (17) in correct direc-
tion. Make sure that the U-ring is intact
before installation.

●

Inverse installation will cause leak of
oil.

●

Make sure that the U-ring is free from
any corrugation or permanent deforma-
tion after installation.

ZX215-1006175

Piston rod

Cushion

Press

Mounting tool

ZX215-1006176

Pressure surface

Hydraulic press

Tool

ZX215-1006177

Press in

Tool

U-groove

8-101

Disassembly and Assembly

4) Installation of buffer ring (16)

NOTE: Make sure that the seal is in-
stalled in correct direction. Inverse in-
stallation can cause high pressure be-
tween the buffer ring (16) and the U-ring
(17), which may lead to deformation or
breakage of oil cylinder.

5) Install the elastic ring (20) to prevent

the fall of the bushing (19).

3. Assembling the piston assembly

1) Installation of seal (14).

NOTE: Install first the O-ring seal and
the one-side guard ring (13) on the pis-
ton. Place the piston on the press. As
shown in the illustration on the right,
the seal (14) is installed with the tools
indicated.

2) Correction of seal (14)

NOTE: Install the seal (14) and the
guard ring (13) on the other side. In
order to prevent the expansion of the
seal (14), a corrector must be used to
correct the seal (14) which has been
stretched during installation. The piston
rod may not be able to go in the cyl-
inder barrel if the seal (14) is not cor-
rected timely.

3) Installation of slide ring (12)

NOTE: Slightly open the slide ring (12)
and install it axially. Excessive opening
of the slide ring (12) can fail installation.

ZX215-1006179

Press

Tool

Block

Press

Corrector

Piston

Tool

O-ring

ZX215-1006173

8-102

Disassembly and Assembly

4. Assembling the piston rod assembly

1) Fix the piston rod (1).

2) Install the cylinder (2) on the piston rod.

NOTE: Make sure that the dust ring lip
or the U-ring lip is not stopped by the
shoulder of any part. Install the cylinder
head and the piston rod with the tools.

3) If the bottom side of cylinder contains

a buffer (not for bucket cylinder), install
the buffer bearing and the buffer seal in
the following order.

4) Let the notched side of the buffer seal

(10) face the piston while installing the
buffer seal (10) in the groove.

5) Install the buffer sleeve (8) according to

the indication in the illustration on the
right.

6) Install the stopper ring in the groove.

Install the elastic ring after the buffer
sleeve (8) is pushed to the bottom. A
rubber hammer should be used for the
tapping job in order to avoid damaging
the piston rod and the buffer bearing.

7) If the head side of cylinder contains a

buffer, install the buffer sleeve (6) and
the buffer seal (23) according to the fol-
lowing order.

8) The piston nut must be installed after

installation of the buffer bearing.

9) The buffer seal (23) must be installed in

the groove, with its notches facing the
piston.

ZX215-1006180

Assembly tool

ZX215-1006181

Gap facing thread direction

Thread

Piston rod

One gap

(2 pcs)

Head end buffer

8-103

Disassembly and Assembly

ZX215-1006183

Rivet

Punch

ZX215-1006182

Gap facing piston side

Rod end buffer

10) The buffer sleeve (6) must be installed

according to the illustration on the right.

11) Tighten the piston nut (5).

Piston nut (arm):

9600 N·m {979.6 kgf·m}

Piston nut (boom and bucket):

6200 N·m {632.6 kgf·m}

NOTE:

●

Insufficient tightening can cause oil
leakage, loose nut and thread break-
age. In addition, excessive tightening
can cause expansion of the buffer shaft
on the extending side or deformation of
piston on the contact side.

●

Thoroughly clean and grease (with ba-
nana oil) the threaded portions of the
piston, nuts and piston rod before tight-
ening the nuts.

12) Treatment of the piston against loosen-

ing

NOTE: After the piston nut (5) is tight-
ened, put in the steel ball (4), tighten
the setscrew (3) and punch to rivet the
two peripheral points.

Setscrew (3):

66.9 N·m {6.8 kgf·m}

8-104

Disassembly and Assembly

5. Install the piston into the cylinder barrel

1) Fix the barrel in a vertical or level man-

ner.

2) Install the piston rod into the cylinder

barrel.

NOTE:

●

xed in a vertical manner, the piston

rod falls into the barrel under its gravity.

●

Make sure that the slide ring does not
fall while the piston is inserted into the
barrel.

6. Tightening of cylinder head

Tighten the cylinder head according to the
sequence shown in the illustration on the
right.

Bolt: 267 N·m {27.2 kgf·m}

7. Install the tubing.

ZX215-1006184

Tool

Nylon sleeve
(2 pcs type)

(Spread the
gaps by 180°)

ZX215-1006185

Tightening sequence

8-105

Disassembly and Assembly

8.28

Work Equipment AS - Remove and Install

1. Disconnect the grease hose (1).

2. Lift the boom cylinder assembly (2). Re-

move the lock bolt (3).

3. Remove the plate (4) and then the pin (5).

NOTE: There are shims installed. Count
the shims and check the thickness. Place
the shims in a safe place.

4. Start the engine and retract the piston rod.

NOTE: Secure the piston rod with a wire
rope in order to prevent the piston from
slipping out. Put the cylinder on a bench or
support. Remove the grease

tting on the

bottom side in the later case. Remove the
other boom cylinder in the same way.

5. Remove the two hoses (6) of bucket cylin-

der and the those (7) of the arm cylinder.

NOTE: Cork the hoses to prevent outflow
of oil. Secure the hoses to the valve side.

6. Remove the inter-connector (8) used for

work lamp.

ZX215T-1006186

ZXT225-1106028

8.28.1 Removal

See “Residual Pressure in Hydraulic Circuit -
Release” on page 6-40.

WARNING

●

Fully extend the arm and the bucket.
L o w e r t h e w o r k e q u i p m e n t t o t h e
ground. Move the hydraulic lockout
control to the LOCK position.

●

Release residual pressure in the hy-
draulic circuit.

8-106

Disassembly and Assembly

7. Lift the work equipment and remove the

plate (9). Remove the pin (10) from the
bottom.

NOTE: There are shims installed. Count
the shims and mark their locations.

8. Lift and disassemble the work equipment

assembly.

Work equipment assembly:

3451 kg

ZX215T-1006188

ZX215T-1006189

8-107

Disassembly and Assembly

8.28.2 Installation

ZX215-1006190

ZX215-1006191

●

Hydraulic oil adding

Add hydraulic oil to the specified level.
Start the engine to circulate the oil in the
hydraulic system, and check the oil level
again. Add more hydraulic oil if necessary.

●

Air bleeding

Bleed the air from travel motor.

For more information, see “Air in Each
Component - Bleed” on page 6-46.

NOTE: Adjust the shim thickness in order
to have a desired clearance (a: 0.5<a<1
mm) between the piston end (12) and the
plate (4).

Standard shim thickness: 1.0 mm and 2.0
mm.

Greasing after assembling the pin:

Grease (supramoly lithium base)

CAUTION

●

Do not put your finger in the pin bore
while aligning the pin bore.

●

Installation is to be performed in the re-
verse order of removal.

NOTE: A clearance (a: 0.5~1.5 mm) shall
be left between the plate and the nut when
tightening the locknut.

Greasing after assembling the pin:

Grease (supramoly lithium base)

8-108

Disassembly and Assembly

8.29 Air Conditioner AS - Remove and Install

1. Drain the coolant.

Coolant: approx. 22.5 L

2. Recover refrigerant from the air-condition-

ing system with the tool (S).

ZX215T-1006192

ZX215T-1006193

Special tools

Part Name

Model

Necessity Qty

Refrigerant

charger

Robinair

34711-2K

●

Refrigerant

charger

Inoue Qing-

Hua

●

8.29.1 Removal

3. Remove the pad (1) on the cab

oor.

CAUTION

●

Disconnect the cable from the negative
(-) post of the battery.

8-109

Disassembly and Assembly

4. Open the left rear cover of the cab with the

ignition key. Remove the outer filter ele-
ment (2).

ZX215T-1006196

5. Remove the fuse box (3) and storage box

(4).

6. Remove outer covering (5).

7. Remove the air conditioner cover (6).

8. Remove the back air duct (7).

9. Remove the left air duct (8).

10. Remove the baf

e (9).

11. Remove the right air duct (10).

ZXT225-1006205

W13092904

Cover

8-110

Disassembly and Assembly

12. Remove the cover (11).

13. Remove the cab's center connector (12).

14. Remove the radio antenna(13).

ZXT225-1006206

15. Remove the connector (14), connector (15)

and air conditioner wiring connection (16).
Remove the two air conditioner relays (17),
three mounting bolts (18). Remove the
electrical mounting plate (19).

16. Remove the air conditioner water pipes (20)

and (21) as well as the dripping tube (22).

ZX215T-1006200

ZXT215-1308207

SANY Crawler Hydraulic Excavator SY195C9, SY205C9, SY215C9, SY225C9. Service Manual - page 37