Cylinder and piston kit for the Stihl MS 461 chainsaw. 52mm bore, 36mm stroke, 76.5cc. Replaces Stihl part number 1128-020-1250. The cylinder is chrome plated. The same kit also fits the Stihl GS 461 concrete and rock cutter, which uses the same top end. IT DOES NOT FIT THE MS 460 OR THE 046. This is the trap on this saw and it is worth reading twice. The MS 460 has the same 52mm bore, the same 36mm stroke and the same 76.5cc displacement. On paper the two engines are identical. Stihl nevertheless gave the MS 460 its own cylinder under part number 1128-020-1221, and the two are not interchangeable. Bore and displacement do not settle fitment here. Read the model off the saw. The MS 440 and 044, for reference, are 50mm and a different part again. EVERY MS 461 VARIANT TAKES THIS CYLINDER. The MS 461 R, RZ, Z, VW, VWZ, RVWZ, Rescue and Magnum all use the same assembly. Those letters mean wrap handle, spark arrestor muffler, carburetor heating and handle heating, and Magnum is a United States market name. None of them changes the top end. RINGS. The piston carries two compression rings in the thinner 1.2 millimeter section, 52 by 1.2mm. The matching Stihl ring number is 1122-034-3000 and the cylinder gasket is 1128-029-2310. Count the rings on the piston you remove and check the groove section before ordering anything else. WHAT IS IN THE KIT, AND WHAT IS NOT. Cylinder and piston. Gaskets and crankshaft seals are not included and both are worth replacing while the engine is open. BEFORE REASSEMBLY, AND A WARRANTY CONDITION. A scored piston is a symptom. On a saw of this displacement the cause is nearly always a lean mixture, from a crankshaft seal that has gone hard, a split or perished impulse line, or an intake boot that has loosened or cracked. Pressure and vacuum test the crankcase and fix the leak before the new top end goes on. The 30 day warranty on this kit is conditional on the saw having been pressure and vacuum checked, for exactly that reason: a new cylinder fitted to an air leak fails the same way the old one did. ON ASSEMBLY. Scuff the plated bore lightly rather than honing it hard, check ring end gap in this cylinder, use a ring compressor, and fit the circlips with the open end turned away from the ports.
- 52MM CYLINDER AND PISTON KIT FOR THE STIHL MS 461 - Replaces Stihl part number 1128-020-1250, which is Stihl's own cylinder with piston for this saw. 52mm bore, 36mm stroke, 76.5cc. The cylinder is chrome plated. It also fits the GS 461 concrete cutter, which shares the same top end.
- IT DOES NOT FIT THE MS 460 OR THE 046, AND HERE IS WHY THAT TRIPS PEOPLE - The MS 460 is also 52mm, also 36mm stroke, also 76.5cc. Identical on paper. Stihl still gave it a different cylinder, 1128-020-1221. Matching the bore and the displacement is not enough on this family. Order by the model on the saw.
- FITS EVERY MS 461 VARIANT - The R, RZ, Z, VW, VWZ, RVWZ, Rescue and Magnum versions all take this same cylinder. Those suffixes are wrap handle, spark arrestor muffler, carburetor heating and handle heating, and none of them changes the top end. Magnum is a US name rather than a mechanical difference.
- TWO RINGS, 52 BY 1.2 MILLIMETER - This piston runs two compression rings rather than one, and they are the thinner 1.2mm section. Count the rings and check the groove depth on the piston you take out. The matching Stihl numbers are 1122-034-3000 for the rings and 1128-029-2310 for the cylinder gasket.
- PRESSURE AND VACUUM TEST THE CRANKCASE - IT IS ALSO A WARRANTY CONDITION HERE - A saw that scored a piston did it for a reason, and on a saw this size the reason is nearly always a lean mixture from a hardened crankshaft seal, a split impulse line or a loose intake boot. The 30 day warranty on this kit requires the saw to have been pressure and vacuum checked.