924 S L4-2479cc 2.5L (1986)
Technical Service Bulletin # 18703
Date: 870306
Cylinder Heads - Tightening Procedure & Service Changes
Subject:
Tightening Procedure for Cylinder Heads
Model
All
Group
1
Part Identifier
1570
Number
8703
March 6, 1987
Cylinder head tightening procedures as well as head gaskets, bolts, nuts and washers have changed for some Porsche models.
The following pages outline current valid repair procedures and replacement parts required for each engine. They are arranged by vehicle model.
924 Model
This technical information replaces all previous instructions concerning the tightening of cylinder heads on 924 vehicles produced from 1977 to 1982
(except Turbo).
The torque angle tightening method in conjunction with the following parts is valid for all 924 naturally aspirated engines since the beginning of 1977
production.
Cylinder Head Gasket
Part Number 047 103 383
Polygon Tooth Head Bolts
Part Number 046 103 385
Washers
Part Number N 901 157 01
Tightening specifications to torque angle method. Tightening is done in two steps:
Step 1: 65 N-m (48 ft. lbs.) Step 2: 180 degrees (1/2 turn)
Important:
Sequencing as shown must be kept for each step. Threads and bearing surfaces of bolts must be lightly lubricated with oil prior to installation. Washers
must not turn while tightening. Create a reference mark if necessary. Replace head bolts at each repair. When using torque angle method, cylinder head
retorque is not necessary.
924 Turbo Model
This technical information replaces all previous instructions concerning the tightening of cylinder heads on 924 Turbo vehicles produced from 1980 to
1982. The following parts are valid for repairs.
Cylinder Head Gasket
Part Number 931 104 337 03