Cylinder Block Assembly (Includes Items 67-71)Specifications Item Description The Cylinder Block Assembly (70004909) is a core component of the engine system on JLG 450AJ and 450A aerial work platforms. This assembly, which includes items 67 71, serves as the main housing for the piston pump assembly and manages fluid displacement and pressure regulation. One cylinder block assembly is required per installation as part of the complete piston pump assembly. Skyworks is an authorized reseller of