Subject: Oil Pressure Relief and Safety Valves Models: 911/930 1978
Bulletin Number: 78 – 03
Oil pressure relief and safety valve springs and screws were modified during 1978 model year beginning with engine numbers as follows:
Vehicle | 49 States | California |
911SC Turbo | 68 2539 688 0290 | 658 1060 688 1179 |
If oil pressure and oil level drop suddenly during high-speed driving, and 1978 vehicle engine number is prior to those listed,

Replace Safety Valve and Pressure Relief Valve parts with new parts shown

Latest part numbers:
Safety Valve | Pressure Relief Valve |
Spring, Part # 901.107.531.00 Screw, Part # 999.064.026.02 | Spring, Part # 930.107.531.01 Screw, Part # 999.064.026.02 Spring Guide, Part # 930.107.533.00 |

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