BUSHING 2T1581 - Caterpillar

High Speed 3516 Engines (25Z, 27Z, 28Z, 29Z)Description of Change: A new bearing housing assembly and a new turbine shaft and wheel assembly are used in turbochargers on high speed 3516 Industrial, Marine and Generator Set Engines, and on 3516 Vehicular Engines for OEM's. The new bearing housing assembly includes an insert ring that contacts the oil seal ring. The oil seal ring is located in a new groove in the new turbine shaft. See illustration. The oil seal ring for the new turbine shaft did not change.
New oil seal around the turbine end of the shaft.The combination of the added insert ring and different location of the ring seal on the new shaft improves oil sealing at the turbine end of the shaft.
The sheet metal 2W1267 Shroud is no longer used with the new turbine sealing design.
Some inserts for the Parts Books and microfiche will show this shroud in the new cartridge groups. It was never used with the new seal and will not fit around the new seal if attempts are made in the field to install it.Adaptable To: Either the new turbochargers (basic), or new cartridges, can be used as direct replacements for the former groups. See Chart A, Chart B, or Chart C. The basic group numbers for the turbochargers are on the nameplate. The turbocharger model numbers ("C" or "W" prefix) did not change. If desired, the former cartridges can be reworked by installing the new bearing housing assembly and the applicable new shaft and wheel assembly. See Chart D. The oil ring seal goes in the outer groove in the new turbine shaft; it will not fit in the inner groove. Do not reuse the 2W1267 Shroud.
There are also several turbochargers available for parts service only of earlier turbochargers used before the listed former turbochargers. See Chart D.