Stihl 4123 · Section A · 1 of 9 · 34 parts

Crankcase, Cylinder

Fits FS 48, FS 52, FS 56.

This assembly is listed with 2 bore sizes — Ø 29 mm (this machine only), Ø 31 mm (also listed for the FS 62, FS 66). Not interchangeable — measure your cylinder before ordering.

No exploded view for this assembly. The catalogue lists its parts without a drawing.

Parts (34)

Pos	Part number	Description	Qty
1	4123 020 2601	Crankcase, fan side	1
2	9380 620 2570	Roll pin 5x12	4
3	9503 003 6320	Grooved ball bearing 6200	2
4	9640 003 0960	Oil seal 10x20x5	2
5	4123 020 2801	Crankcase, starter side	1
6	4125 030 0400	Crankshaft	1
7	0000 958 1018	Shim 0.1 mm	1
8	0000 958 1019	Shim 0.2 mm	1
9	9022 341 1050	Spline screw IS-M5x25	4
10	4123 084 2200	Guard option	1
11	4123 084 2205	Guard option	1
12	4123 029 2300	Cylinder gasket	1
13	4125 022 0500	Cylinder Ø 29 mm	1
14	4125 034 0500	Piston Ø 29 mm	1
15	4125 034 3000	Piston ring	2
16	4118 034 1500	Piston pin	1
17	9463 650 0805	Snap ring 8x0.7	2
18	4123 030 0400	Crankshaft	1
19	9512 003 1840	Needle cage 8x11x12	1
20	4123 022 0500	Cylinder Ø 31 mm	1
21	4123 034 0500	Piston Ø 31 mm	1
22	4123 034 3000	Piston ring Ø 31x1.3 mm	2
23	4112 034 1500	Piston pin	1
24	9463 650 0800	Snap ring 8x0.7	2
25	9022 341 0980	Spline screw IS-M5x16	4
26	0000 400 7000	Spark plug NGK BPMR7A	1
26	1110 400 7005	Spark plug Bosch WSR 6 F not illustrated	1
27	0000 998 0606	Torsion spring	1
28	1106 405 1000	Spark plug boot → replaced by 1128 405 1000, 1128 405 1000 TI 30/1995	1
Not numbered on the diagram — assemblies, kits and options
—	4125 020 1200	Cylinder with piston Ø 29 mm	1
—	4125 030 2000	Piston Ø 29 mm	1
—	4123 020 1200	Cylinder with piston Ø 31 mm	1
—	4123 030 2000	Piston Ø 31 mm	1
—	0783 830 2000	Tube of sealant Dirko HT red not illustrated	1

2012 service parts catalogue. Parts are not interchangeable across engine series — check yours before ordering.

Wrong number or missing part for the FS 48, FS 52, FS 56? Report a correction →