Section 2 - Oil Cooler Repairs
From Model '87 engine numbers:43 H 02505 924S, 944 manual transmission
43 H 60517 924S, 944 automatic transmission
42 H 00522 944S
the oil cooler mounting was modified as follows:
1. Plastic washer installed between housing and oil cooler.
2. Housing - Guide drilling reworked.
3. Adjustment shims between cooler and crankcase installed.
4. Rubber ring (always replace when servicing).
When repairing earlier cars, the new type housing, plastic washer, and adjusting shims must be used.
To determine if the oil cooler housing is the latest version, and to help prevent needless housing replacement, inspect as shown.
New Oil Cooler O-Rings
The sealing O-rings (A, figure 1) located on the oil cooler of normally aspirated cars and on the connecting pipe of the oil thermostat housing of Turbo cars, have been changed. The new version O-ring is now green in color (formerly red). When repairing, use ONLY the new version green O-rings PN 999 707 043 40.
The new version O-rings are installed from the following engine number.
46 J 06772 924S, 944 manual trans.
46 J 61599 924S, 944 auto trans.
42 J 01420 944S
45 J 01753 944 Turbo
47 J 00899 944 Turbo S
Please note that the O-ring "A" in Fig. 1, is also installed in 944 Turbo cars. There are two Orings on a short connecting pipe in the same place as they are found on normally aspirated cars.
Repair Hints
Pre-assemble Oil Cooler:
Install new version O-rings onto oil cooler. Install plastic washer onto cooler guide boss (use light grease to hold washer in place if necessary). Lubricate cooler O-rings with oil to prevent rolling and insert cooler into housing. Use straightedge on housing and determine distance between oil cooler guide boss and straightedge (see photo). With shims installed, measurement should be 0 +/- 0.25 mm. The oil cooler housing gasket is NOT included in the measurement. Thickness of one shim is 0.5 mm.
Before installing cooler assembly, mount a new rubber ring (arrow 4) onto crankcase and hold in place with light grease or Curil.
Position preassembled oil cooler housing onto crankcase and center the housing with the appropriate centering tool 9215 83-86 944, 944 Turbo and early 87 924S; 9262/1 87 on 924S, 944, 944S, 944 Turbo. Refer to the oil pressure relief valve application information in this bulletin for centering tool information.
Coat the pressure relief valve O-ring and outer surface with oil to prevent binding during installation.
Important Note:
In case of leaks at the oil cooler, the cooling system needs to be flushed. If there is engine oil in the coolant or if coolant has entered the engine lubrication system, the connecting rod bearings must be replaced. Always replace connecting rod nuts at each repair also.