Alternator - A/C Compressor Belt Squeal On Cold Start

August 25, 1992

Model
911 Turbo

Part Identifier
8725

Group
8

Number
9203

Subject:
Alternator - A/C Compressor Belt Squeal on Cold Start

ATTENTION:
Service Manager/Service Technician

This bulletin replaces Technical Bulletin, Group 8, Number 9203, dated 6-30-92.

Models Affected:
911 Turbo 1991 (M) and 1992 (N) models

Concern:
Squeal from alternator - A/C compressor belt after cold start of the engine.

General Information:

To eliminate belt squeal during cold start, the alternator - A/C compressor belt is now longer and routed differently over the drive pulleys. The new belt is identified by the marking "6k 1554" printed on the belt (See Figure 1).

Parts Information:
New version belt Part Number 999 192 365 50
Former version belt Part Number 999 192 356 50 (no longer available)

New alternator - A/C compressor belts were introduced into vehicle production as of April 29, 1992, beginning with engine number 61 N 01442 M30.69.

Repair Information:
When complaints of squeal from the alternator drive belt are made, or when replacing the former version belt, the new version belt must be installed and the tension set with special tool 9201.

1. The engine must be cold.

2. Install new version belt following the routing shown in Figure 2.

3. Remove the circlip retaining the rollers to the measuring pin of special tool 9201 (Figure 3) and remove rollers.

4. Measure the belt tension at the arrow location shown in Figure 2 and set the tension according to the belt thickness using the values below:

Belt thickness Tool 9201 scale units

5.0 - 5.3 mm 3.0 scale units
5.4 - 5.5 mm 4.0 scale units
5.6 - 5.8 mm 4.5 scale units

If the minimum value belt thickness of 5.0 mm cannot be obtained, a thickness (feeler) gauge may be inserted between the belt and special tool 9201 measuring pin. Do not exceed a total belt thickness of 5.8 mm.

*Note:
Belt thickness can be measured using a vernier caliper. Measurement should be taken at the arrow location in Figure 2.

3. Start the engine and accelerate lightly two-to-three times. Turn off the engine and recheck the belt tension. Readjust if necessary.

9228porsche01

June 30, 1992

Model

911 Turbo

Group

8

Part Identifier

8725

Number

9203

Subject:
Alternator - A/C Compressor Belt Squeal on Cold Start

ATTENTION:
Service Manager/Service Technician

Models Affected:
911 Turbo 1991 (M) and 1992 (N) models

Concern:
Squeal from alternator - A /C compressor belt after cold start of the engine.

General Information:
To eliminate belt squeal during cold start, the alternator - A/C compressor belt is now longer and routed differently over the drive pulleys. The new belt is identified by the marking "6k 1554" printed on the belt.

Parts Information:
New version belt Part Number 999 192 365 50
Former version belt Part Number 999 192 356 50 (no longer available)

Repair Information:
When complaints of squeal from the alternator drive belt are made, or when replacing the former version belt, the new version belt must be installed and the tension set with special tool 9201.

1. The engine must be cold.

2. Install new version belt following the routing shown in Figure 2.