Komatsu G451/G4500 User manual

2847-93120(111)
G451/G4500
G5000
CHAIN SAW
Nov. 2001
NOTE :
1. Use KOMATSU ZENOAH genuine parts specified in the parts list for repair and/or replacement.
2. KOMATSU ZENOAH does not warrant the machines, those which have been damaged by the use
of any parts other than those specified by the company.
3. When placing orders of parts for repair and/or replacement, check if the model name and the serial
number are suitable to those specified in the parts list, then use parts number described in the
parts list.
4. The contents described in the parts list may change due to improvement.
5. The parts for the machine shall be supplied within ten (10) years after the machine is discontinued.
[It is possible that some specific parts may be subject to change of their delivery term and list price
within the limit of ten (10) years after the machine is discontinued. And it is also possible that some
parts may be available even after the limit of ten (10) years.]
APPLICABLE SERIAL NUMBERS : 100101 and up

Fig.1 POWER UNIT
G451/G4500/G5000

Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2670-12113 Cylinder 1 ø43
2 2810-14110 Inlet Pipe 1
3 2817-14121 Gasket (K2810-06012) 1 Kit
4 2670-14130 Screw M5x10 1
5 2880-14150 Inner Guide 1
6 2670-14311 Bracket 1
7 2670-14320 Screw M5x14 2
8 2880-14350 Spacer 1
9 2880-14360 Gasket 1
10 2670-14211 Gasket, Cylinder (K2810-06012) 1 Kit
11 2850-14220 Bolt, Cylinder M5x20 4
12 2810-15220 Bolt, Muffler M5x83 2
13 2850-15230 Nut, Muffler M5 2
14 2810-15113 Muffler 1
15 2670-14130 Screw M5x10 1
16 3356-15210 Gasket, Muffler (K2810-06012) 1 Kit
17 2810-15310 Cover 1
18 2810-2100A Crankcase Assembly 1
19 3356-21130 • Spring Pin 3
20 T4012-21240 • Bearing 15x35x11 2
21 04065-03515 • Snap Ring ø35 1
22 2670-21210 • Oil Seal 15x35x4.5 1
23 2670-21220 • Oil Seal 15x28X4.5 1
24 2616-21230 • Stud 2
25 2670-21250 • Elbow 1
26 2810-22511 • Stopper 1
27 2810-22521 • Stopper 1
28 2670-21311 • Gasket, Case (K2810-06012) 1 Kit
29 2670-21320 Screw M5x25 5
30 2810-22210 Pipe 3x7x105 1
31 3310-82230 Clip 1
32 2810-22411 Matte 1
33 2670-41114 Piston ø43 1
34 2670-41211 Piston Ring ø43 2
35 3350-41310 Piston Pin8x11x34.5 1
36 3350-41320 Snap Ring 2
37 1400-41410 Needle Bearing 11x15x12.3 1
38 2670-41510 Washer 2
39 2880-42001 Crankshaft Complete 1
40 1000-43240 Key 1
41 2810-06012 Gasket Kit 1
Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2880-12111 Cylinder 1 ø45
2 2880-14111 Inlet Pipe 1
3 2880-14120 Spring
5 2880-14150 Inner Guide 1
6 2670-14311 Bracket 1
7 2670-14320 Screw M5x14 2
8 2880-14350 Spacer 1
9 2880-14360 Gasket 1
10 2670-14211 Gasket, Cylinder (K2810-06012) 1 Kit
11 2850-14220 Bolt, Cylinder M5x20 4
12 2810-15220 Bolt, Muffler M5x83 2
13 2850-15230 Nut, Muffler M5 2
14 2810-15113 Muffler 1
15 2670-14130 Screw M5x10 1
16 3356-15210 Gasket, Muffler (K2810-06012) 1 Kit
17 2810-15310 Cover 1
18 2810-2100A Crankcase Assembly 1
19 3356-21130 • Spring Pin 3
20 T4012-21240 • Bearing 15x35x11 2
21 04065-03515 • Snap Ring ø35 1
22 2670-21210 • Oil Seal 15x35x4.5 1
23 2670-21220 • Oil Seal 15x28X4.5 1
24 2616-21230 • Stud 2
25 2670-21250 • Elbow 1
26 2810-22511 • Stopper 1
27 2810-22521 • Stopper 1
28 2670-21311 • Gasket, Case (K2810-06012) 1 Kit
29 2670-21320 Screw M5x25 5
30 2810-22210 Pipe 3x7x105 1
31 3310-82230 Clip 1
32 2810-22411 Mat 1
33 2880-41110 Piston ø45 1
34 2880-41210 Piston Ring ø45 2
35 2880-41310 Piston Pin 7.4x11x37.5 1
36 3350-41320 Snap Ring 2
37 1400-41410 Needle Bearing 11x15x12.3 1
38 2670-41510 Washer 2
39 2880-42001 Crankshaft Complete 1
40 1000-43240 Key 1
41 2810-06012 Gasket Kit 1
Fig.1 POWER UNIT
G451/G4500 G5000

Fig.2 IGNITION,STARTING
G451/G4500/G5000

Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2670-71101 Rotor assembly 1
2 1850-75220 • Ratchet 2
3 2670-71130 • Spring 2
4 0308-00040 • Ring 2
5 3350-43231 Nut M8 1
6 0290-20820 Washer M8 1
7 2880-71300 Coil Assembly 1
8 2810-71204 • Coil Complete 1
9 2810-71220 • • Cord 1
10 2670-71230 • • Grommet 1
11 2810-72110 • Plug cap 1
12 1400-72121 • Spring 1
13 2670-71320 • Tube 1
14 2810-71250 Grommet 1
15 2670-14220 Screw M5x20 2
18 2670-71510 Cord 1
19 2880-71600 Switch assembly 1
20 2810-71610 • Switch 1
21 2670-71621 • Switch Cover 1
22 2880-71630 • Plate 1
23 2670-14130 Screw M5x10 1
24 3699-90431 Spark plug (NGK BPM7Y) 1
25 2810-21270 Plate 1
26 0260-30410 Screw M4x10 2
27 2881-75000 Starter assembly 1
28 2810-75110 • Recoil case complete 1
29 2810-75120 • Guide 1
30 2810-75150 • Boss 1
31 2670-75212 • Reel 1
32 3317-75300 • Spring complete 1
33 2670-75411 • Rope 1
34 T2041-75420 • Knob 1
35 T2041-75431 • Collar 2
37 2881-75440 • Spring B
38 1400-86280 • Washer 1
39 2670-14220 • Screw 1
40 2880-75600 Fan cover complete 1
41 2670-75613 • Cover 1
42 2880-75620 • Sheet 1
43 2670-14320 Screw 4
44 2811-75132 Label, Recoil 1
45 2881-98611 Snow protector 1 OP
Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2670-71101 Rotor assembly 1
2 1850-75220 • Ratchet 2
3 2670-71130 • Spring 2
4 0308-00040 • Ring 2
5 3350-43231 Nut M8 1
6 0290-20820 Washer M8 1
7 2880-71300 Coil Assembly 1
8 2810-71204 • Coil Complete 1
9 2810-71220 • • Cord 1
10 2670-71230 • • Grommet 1
11 2810-72110 • Plug cap 1
12 1400-72121 • Spring 1
13 2670-71320 • Tube 1
14 2810-71250 Grommet 1
15 2670-14220 Screw M5x20 2
18 2670-71510 Cord 1
19 2880-71600 Switch assembly 1
20 2810-71610 • Switch 1
21 2670-71621 • Switch Cover 1
22 2880-71630 • Plate 1
23 2670-14130 Screw M5x10 1
24 3699-90512 Spark plug (NGK BPM8Y) 1
25 2810-21270 Plate 1
26 0260-30410 Screw M4x10 2
27 2881-75000 Starter assembly 1
28 2810-75110 • Recoil case complete 1
29 2810-75120 • Guide 1
30 2810-75150 • Boss 1
31 2670-75212 • Reel 1
32 3317-75300 • Spring complete 1
33 2670-75411 • Rope 1
34 T2041-75420 • Knob 1
35 T2041-75431 • Collar 2
37 2881-75440 • Spring B 1
38 1400-86280 • Washer 1
39 2670-14220 • Screw 1
40 2880-75600 Fan cover complete 1
41 2670-75613 • Cover 1
42 2880-75620 • Sheet 1
43 2670-14320 Screw 4
44 2881-75131 Label, Recoil 1
45 2881-98611 Snow protector 1 OP
Fig.2 IGNITION,STARTING
G451/G4500 G5000

RECOIL STARTER of G451AVS
The difference between G451 and G4500 is only the recoil starter.
This is the parts list of G451 recoil starter.
key#
part number
discription
Q'ty/unit
A2880-75002 starter assy 1
B2810-75110 ・case 1
C2810-75120 ・guide 1
D2810-75150 ・boss 1
E2670-75211 ・reel 1
F3317-75300 ・spring comp 1
G2670-75410 ・rope 1
H1400-75170 ・washer 1
I3310-75431 ・washer 1
J1400-86280 ・screw 1
K2670-14220 ・screw 1

Fig.3 HANDLE
G451/G4500/G5000

Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2810-32100 Left handle complete 1
2 2671-32210 Screw M5x19 BT 4
7 2810-33007 Right handle assembly 1
8 3330-33250 • Stopper 1
9 3310-33262 • Spring 1
10 3310-33271 • Knob 1
11 2810-33280 • Damper (A) 1
12 2670-75520 • Screw 1
13 2810-33210 • Gasket 1
14 2670-33311 • Throttle lever 1
15 3356-33321 • Throttle spring 1
16 04025-00524 • Spring pin ø5.2x24 1
17 3356-33352 Arm 1
18 2670-34110 Grip cover 1
19 2671-32210 Screw M5x19 BT 1
20 2810-25210 Chain catcher 1
21 2670-14320 Screw M5x14 1
22 2880-35111 Damper 3
23 2670-35120 Screw M5x16 BT 4
24 2810-35150 Damper cap 3
25 2881-35110 Spring 1
26 2881-35120 Spacer 4
27 2880-35211 Damper 2
28 3350-35170 Bolt 2
29 2880-35250 Cap 2
Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1 2880-32101 Left handle complete 1
2 2671-32210 Screw M5x19 BT 4
3 2880-32250 Bracket 1
4 2670-14130 Screw M5x10 1
5 2880-32270 Screw M5x8 1
6 2880-31211 Damper 1
7 2810-33007 Right handle assembly 1
8 3330-33250 • Stopper 1
9 3310-33262 • Spring 1
10 3310-33271 • Knob 1
11 2810-33280 • Damper (A) 1
12 2670-75520 • Screw 1
13 2810-33210 • Gasket 1
14 2670-33311 • Throttle lever 1
15 3356-33321 • Throttle spring 1
16 04025-00524 • Spring pin ø5.2x24 1
17 3356-33352 Arm 1
18 2670-34110 Grip cover 1
19 2671-32210 Screw M5x19 BT 1
20 2810-25210 Chain catcher 1
21 2670-14320 Screw M5x14 1
22 2880-35111 Damper 3
23 2670-35120 Screw M5x16 BT 4
24 2810-35150 Damper cap 3
25 2881-35110 Spring 1
26 2881-35120 Spacer 4
27 2880-35211 Damper 2
28 3350-35170 Bolt 2
29 2880-35250 Cap 2
Fig.3 HANDLE
G451/G4500 G5000

Fig.4 FUELING SYSTEMS
G451/G4500/G5000

Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1A 2810-31115 Cylinder cover 1
3 2670-14320 Screw M5x14 5
4 2854-31513 Label 1
5 2810-83305 Cleaner cover complete 1
6 3356-83322 • Knob 1
7 3388-83340 • Gasket, cap 1
8 2810-83500 • Air cleaner complete 1
9 2810-83520 • • Seal 1
10 1600-33130 • Screw 1
11 2810-83410 • Grommet, Air cleaner 1
12 2810-83101 Air cleaner complete 1
13 2813-31210 Label 1
14 2880-82310 Guide ( I ) 1
15 2880-82350 Guide (HL) 1
16 2880-82102 Manifold complete 1
17 2810-82141 Supporter 1
18 2880-82210 Screw M5x52 1
19 2880-82410 Choke rod 1
20 2670-82421 Grommet, Choke 1
21 2670-82430 Guide 1
22 2880-82511 Throttle rod 1
23 2810-82520 Grommet, throttle 1
24 2810-34303 Fuel pipe assembly 1
25 2810-34312 • Fuel pipe 1
26 2810-34350 • Collar 1
27 3302-85400 • Filter assembly 1
28 2670-34401 Tank cap assembly 1
29 2670-34430 • Gasket, Tank cap 1
30 2670-34500 Breather Assembly 1
31 3350-34540 • Pipe 1
32 1260-85460 • Clip 1
33 T2041-75810 Label 1
34 2811-98501 Air cleaner complete 1 OP(Felt)
Q'TY
Key# PART NUMBER DESCRIPTION NOTE
/UNIT
1B 2880-31101 Cylinder cover 1
2 2880-31120 • Nut 1
3 2670-14320 Screw M5x14 5
4 2854-31513 Label 1
5 2810-83305 Cleaner cover complete 1
6 3356-83322 • Knob 1
7 3388-83340 • Gasket, cap 1
8 2810-83500 • Air cleaner complete 1
9 2810-83520 • • Seal 1
10 1600-33130 • Screw 1
11 2810-83410 • Grommet, Air cleaner 1
12 2810-83101 Air cleaner complete 1
13 2813-31210 Label 1
14 2880-82310 Guide ( I ) 1
15 2880-82350 Guide (HL) 1
16 2880-82102 Manifold complete 1
17 2810-82141 Supporter 1
18 2880-82210 Screw M5x52 1
19 2880-82410 Choke rod 1
20 2670-82421 Grommet, Choke 1
21 2670-82430 Guide 1
22 2880-82511 Throttle rod 1
23 2810-82520 Grommet, throttle 1
24 2810-34303 Fuel pipe assembly 1
25 2810-34312 • Fuel pipe 1
26 2810-34350 • Collar 1
27 3302-85400 • Filter assembly 1
28 2670-34401 Tank cap assembly 1
29 2670-34430 • Gasket, Tank cap 1
30 2670-34500 Breather Assembly 1
31 3350-34540 • Pipe 1
32 1260-85460 • Clip 1
33 T2041-75810 Label 1
34 2811-98501 Air cleaner complete 1 OP(Felt)
Fig.4 FUELING SYSTEMS
G451/G4500 G5000