Champion M1387 Crankshaft Assembly For R70A Pumps

Champion M1387 is a machined OEM crankshaft assembly built for Champion R70A pumps, the Champion R-Series air compressors in the 20–30 HP range. Identified by part number M1387, this component is listed in Champion replacement-part catalogs and manuals as the crankshaft for the R70/R70A family and is supplied as an OEM, machined replacement to restore original geometry and timing. Some distributor listings describe the R70A crankshaft as balanced, underscoring its design to maintain smooth operation when used in R-Series configurations. The R70A pump is used on multiple Champion R-Series models, including BR20, HR20-12, HR20-24, HR20D-24, BR25, HR25-12, HR25-24, HR25D-24, BR30, HR30-12, HR30-24, and HR30D-24, making M1387 a suitable OEM option for technicians servicing those units. Choosing the M1387 crankshaft ensures compatibility with the connecting rod assemblies and main bearings specified by Champion for R70A pumps, supporting reliable timing and long-term operation within the R-Series ecosystem.