
ENGINE PARTS - MODEL TB490BC
4-CYCLE GAS TRIMMER
PPN - 41BDT49C063
1
46
45
49
50
51
52
54
53
47
48
89
55
57
58
62
88
87
59
60
68
73
74
75
72
71
70
67
76
77
78
79
80
69
81
82
83
84
82
85
66
65
64
63
56
2
3
16
17
18
19
20
21
22
23
25
26
86
27
30
31
33
36
4
5
8
10
6
7
9
13
11
38
12
15
14
39
37
40
41
42
43
45
29
32
35
34
61
Issued 9/02
24

ENGINE PARTS - MODEL TB490BC 
4-CYCLE GAS TRIMMER
PPN - 41BDT49C063
Item Part No. Description
46 791-181247 Palnut 
47 753-1199 Recoil Pulley 
48 753-04286 Recoil Spring 
49 791-182366 Nut Clip 
50 791-181079 Pull Handle 
51 791-611061 Rope Guide 
52 791-613103 Rope 
53 791-181020 Starter Housing Screw 
54 753-1237 Starter Housing Assembly (includes 46-52) 
55 791-182368 Clutch Washer 
56 753-1238 Clutch with Spacer 
57 791-153592 Clutch Drum 
58 753-1239 Clutch Cover 
59 791-145569 Anti-Rotation Screw 
60 753-1240 Screw 
61 753-1241 Nut 
62 791-181345 Clutch Cover Screws 
63 753-04298 Ignition Module with Screws 
64 791-181065 Spacer 
65 753-04299 Flywheel 
66 791-182743 Shroud Assembly with Screws 
67 791-182376 Crankcase Assembly (includes 68 & 69) 
68 791-182375 90° Elbow 
69 791-182379 Breather Hose 
70 791-181015 Cam Gear 
71 753-1242 Cam Follower Set 
72 791-181013 Cam Bracket 
73 791-181012 Cam Bracket Screw 
74 791-181040 Valves, Intake and Exhaust 
75 791-182374 Cylinder Gasket 
76 791-181018 Oil Pan Gasket 
77 791-182377 Oil Pan (includes 76 & 78) 
78 791-181020 Oil Pan Screw 
79 753-04041 Dipstick Assembly (includes 84) 
80 791-182290 O-Ring 
81 791-181009 Connecting Rod 
82 791-181008 Wrist Pin Button 
83 753-1243 Piston 
84 791-181006 Wrist Pin 
85 791-182295 Piston Ring Set 
86 791-182409 Washer 
87 791-181861 Screw 
88 791-612468 Compression Spring 
89 791-182537 Grommet
* 791-180852B Spark Plug 
* 753-1245 Short Block Assembly (includes 3-15, 66-85) 
* 791-180142 Starter Pawl Repair Kit 
* 791-182156 Carburetor Repair Kit 
* 753-1248 Gasket Diaphragm Repair Kit
* Parts not shown
Item Part No. Description
1 753-04083 Engine Cover 
2 791-182339 Engine Cover Screws 
3 791-181025 Valve Cover Screw 
4 791-182098 Valve Cover 
5 791-182099 Valve Cover Gasket 
6 791-182340 Rocker Adjustment Nut 
7 791-182101 Rocker Arm Pivot 
8 791-182100 Rocker Arm
9 791-182341 Rocker Arm Stud 
10 791-182103 Valve Spring Retainer 
11 791-181038 Valve Spring 
12 791-182102 Push Rod Guide 
13 791-181033 Push Rod 
14 791-182745 Cylinder Head (includes 9 & 12) 
15 791-182344 Cylinder Screw 
16 791-182345 Intake Baffle 
17 791-182749 Carburetor Mount Gasket 
18 791-181034 Nut 
19 791-182347 Carburetor Mount (includes 18) 
20 791-182348 Carburetor Mount Screw 
21 791-182732 Carburetor Gasket 
22 753-04296 Carburetor with Primer 
23 791-181751 O-Ring, Carburetor 
24 753-04305 Air Filter/Choke Cover Assembly
(includes 27) 
25 791-182097 Breather Tube 
26 791-181750 Air Filter Mounting Screw 
27 791-181757 Air Filter 
28 753-04316 Air Filter Cover 
29 753-1229 Fuel Cap 
30 791-182352 Fuel Return Line 
31 791-182353 Fuel Pick-Up Line with Filter 
32 791-181080 Screw 
33 791-182354 Washer 
34 753-1230 Fuel Tank Assembly (includes 29-31) 
35 791-182356 Fuel Tank Shield 
36 753-04297 Throttle Cable 
37 791-182358 Muffler Baffle 
38 791-181048 Muffler Gasket 
39 791-182359 Muffler (includes 38, 40-42) 
40 791-180890 Spark Arrestor Screen 
41 791-181045 Screen Cover 
42 791-181046 Screw 
42 791-182361 Muffler Mounting Screw 
44 753-04092 Muffler Cover 
45 791-182804 Switch Wire Assembly
Issued 9/02

BOOM AND TRIMMER PARTS - MODEL TB490BC
4-CYCLE GAS TRIMMER
PPN - 41BDT49C063
Item Part No. Description
1 791-00040 Throttle Housing and Trigger Assembly (includes 2-4) 
2 791-00041 Throttle Trigger Lock-Out 
3 791-00042 Throttle Trigger 
4 791-182690 Throttle Trigger Spring 
5 791-182405 Switch Assembly 
6 791-610327 Harness Clip 
7 753-1247 Upper Drive Shaft Housing Assembly 
8 791-181099 J-Handle Assembly
9 791-683295 Handle Bracket Assembly (includes 10-15) 
10 791-181811 Screw 
11 791-181812 Upper Handle Clamp 
12 791-181813 Middle Handle Clamp 
13 791-181814 Lower Handle Clamp 
14 791-181815 Nut 
15 791-145569 Anti-Rotation Screw 
16 753-1190 EZ-Link Coupler (includes 16-19) 
17 791-182057 Screw 
18 791-181617 Bolt 
19 791-181981 Adjustment Knob 
20 791-181886 Knob Retaining Nut 
21 791-182541 Lower Drive Shaft Housing Assembly 
22 791-613300 Lower Flexible Drive Shaft 
23 791-182200 Shield Mount Screw Assembly 
24 791-182193 2 piece Gearbox Assembly (includes 25-28) 
25 791-182195 Gearbox Screw 
26 791-145569 Anti-Rotation Screw 
27 791-147492 Blade Shield/Shield Mount 
28 791-182196 Blade Driver 
29 791-683304 Shield Mounting Screw 
30 753-1191 Shield and Blade Assembly (includes 31) 
31 791-682061 Blade Assembly 
32 791-147490 Retaining Washer 
33 791-612483 Spool Shaft 
34 791-683301 Outer Spool and Eyelet Assembly 
35 791-612026 Retainer 
36 791-610636B Spring 
37 791-147495 Inner Reel 
38 791-180814B Bump Head Knob Assembly 
39 791-145873B 4-Tooth Blade 
40 791-181699 Nut
* 791-180014B Blade Retaining Kit (includes 32 & 40) 
* 791-613226 Locking Rod Tool 
* 791-682075B Shoulder Harness
2
Piece Gearbox Assembly Parts – Item 24
41 791-182191 Left Housing 
42 791-182192 Right Housing 
43 791-182194 Pinion Gear Assembly 
44 791-182199 Output Shaft Bushing 
45 791-182198 Output Shaft Gear 
46 791-182197 Output Shaft Assembly
(includes 44 & 45)
47 753-1159 O-Ring
Optional Accessories
* 753-1160 Reel and Line Assembly 
* 753-1161 Bump Head Assembly
(includes 33-38)
* Items Not Shown
15
21
22
23
28
28
25
25
26
29
27
31
24
24
30
35
33
39
34
32
31
20
37
36
32
38
40
1
1
5
11
12
13
14
10
9
8
7
6
4
3
2
44
45
42
42
26
43
46
16
17
18
19
25
47
Issued 9/02
23