OTTO Excavator Parts Tcm 4Fe1 Cooling Water Bypass Pipe 5093611520 509361-1520 5-09361152-0 For Isuzu Durable 5-09361152-0 pipe fits OTTO Tcm & Isuzu 4Fe1. Resists mining dust/heat, pressure-stable. Ensures steady engine cooling for non-stop heavy work.