2013/12/18 Caterpillar

Engine:

G3520C (S/N: GZB1-UP; GZN1-UP; RLP1-UP; LGS1-UP)

G3520E (S/N: GZE1-UP; GZH1-UP)

Description of Change: New main rotor, bearing sleeve, bearing retainer bar, and cable lugs are now available for Gas Generator Sets packaged with 2650 Frame High Voltage Generators.

The new components of the Generator sets (276-0473 Generator Gp and 276-0475 Generator Gp ) have the following improved features:

• Rotor winding insulation is strengthened resulting in greater durability.

• Rotor has heat sink technology implemented that reduces temperature rise approximately 15° C (59° F) to 20° C (68° F)

• Bearing sleeves are constructed with an external surface of greater hardness that reduces wear.

• Cable lugs are of stronger construction.

• Bearing retainer bars are larger, thus less susceptible to loosening.

Adaptable To: New part numbers of wear sleeve, ring terminal, bar retainer, and rotor assembly replaces the former part numbers used in high voltage Generator Sets.

Required Parts

Refer to the Table 1 listing out the new part numbers that replaces the former part numbers:

Rework Procedure

If high linear vibration, high excitation current, low main rotor resistance, or unsymmetrical PMG winding spacing is identified, measure individual main rotor pole resistances with micro-ohmmeter. If pole resistance variation is greater than 10%, it is recommended to replace main rotor, bearings, and drive end bearing sleeve. Also, inspection of cable lugs and bearing retainer bar integrity is recommended.

New main rotor, bearing sleeve, bearing retainer bar, and cable lugs are adaptable to the Generator Sets that are listed in the Table 2.