Has a 55mm stroke. Campbell Hausfeld VT2030, VT4723, VT4923 Twin Cylinder 3.7HP VT Pump. Recommended for 240V and gas units. Same pump as VT490000SJ, but WITH flywheel, Note: New style pump has only one air line coming off of pump head. If your original pump had two outlets, order our CTD1238ADAPTKIT which will allow you to re-route the smaller bleeder line.
The flywheel is the compressor pump’s pulley, which the belt attaches to and drives the crankshaft. Be sure the flywheel and motor/engine pulley is aligned, as a misaligned pulley and flywheel can damage the pump and motor/engine. Replace if cooling fins are missing. Most flywheels have a specific rotation (usually C.C.W. when looking directly at the flywheel) so be sure the flywheel is installed correctly when replacing it to efficiently cool the pump.