Service Information: New compressor with greater displacement

 The compressors currently installed in Unimog model series with a displacement of 238 cm3 (Euro III Standard) and 352 cm3 (Euro IV Standard, Euro V Standard) have been replaced by a compressor with a displacement of 393 cm3. This compressor is a newly developed version which has been designed specifically for use in the Unimog. The series production breakpoint for this compressor was in August 2012 with vehicle identification end number 230816.
As part of ongoing technical developments of the compressor with 393 cm3 displacement, model series 405 with engine 902, 906, a resonator box has also been installed in the compressor's air intake line since January 2013. The_series production breakpoint shall be with vehicle identification end number 232761.

G13.30-3137-02

G13.30-3140-02

Features of new compressor:

 Displacement 393 cm3

 Piston diameter 100 mm (previously 85 mm)

 Retrofit capable for vehicle with Euro III standard, Euro IV standard (note exceptions), Euro V standard

 We recommend installation of the 393 cm3 compressor in vehicles with multiple damage to the cylinder heads as well as on vehicles with high air requirement (e.g. trailer operation, pneumatically-powered implements and bodies, etc.).
To prevent unscheduled workshop visits, preventive replacement of the compressor may also be necessary. If, in such instances, the plant is called on to contribute to the costs, cost settlement per ESKULAB should be queried.


The required part numbers and other details concerning conversion to the above-mentioned compressor are available in the work instructions (SM13.30-G-0002B Conversion to compressor with larger displacement). The document is stored in the WIS.
The Service Information SI13.30­G­0004B "Conversion to compressor with larger displacement" is hereby rendered invalid.

Information on repairs:

Observe the assembly instructions and tightening specifications! The work instructions in the WIS have been updated accordingly.

If because of a damage/repair case the compressor has to be replaced, only the new version may be installed.

Exception: Model 405 with engine 902.935, 906.935/955 and power hydraulics code H63/H64/H65* in combination with code H93 or H94*:

Collision of compressor cylinder head with hydraulic line.

Exception: Model 437.42/43 up to vehicle identification end number 211454 with engine 904.952/953, 924.916:

Collision of compressor coolant line with cab floor.

* Code designations:

Code H63 (VarioPower (power hydraulics), closed circuit)

Code H64 (VarioPower (power hydraulics), open circuit)

Code H65 (VarioPower (power hydraulics), closed + open circuit)

Code H93 (Front pressure and return line, hydraulic circuit 3)

Code H94 (Front pressure and return line, open circuit)

Important additional operations:

Unimog model 405.102/103/122/123/200/201/220/221

When converting to the new compressor, on vehicles with engine 902.923/924/935, 906.935/955, the resonator box must also be installed into the air intake duct.

Unimog model 405.050/101/103/121/123/201/221

When converting to the new compressor, vehicles up to vehicle identification end number 227666 must have a pressure limiting valve installed in the high-pressure control circuit of the compressed-air brake system. See Service Information SI42.60­ G ­0011A as well as work instructions AN42.60­ G ­0014B or AN42.60­ G ­0014BG.

 The variant parts list (SAA) is to be updated in the vehicle documentation (VeDoc) in accordance with the following table (Replacement of compressor with larger displacement overview) once the repair has been completed. The vehicle or engine data in VeDoc must be modified in line with this table.