Porsche 928 Workshop Manual page 238

15
Engine/Cylinder Head, Valve Drive 928
CHECKING AND ADJUSTING
INSTALLATION
LENGTH OF VALVE
SPRINGS (32-VALVE
ENGINES)
VALVE
SPRINGS,
'87 MODELS ONWARD
ENGINE TYPE M 28. 41/42
Note:
It
is essential to ensure that the
correct valve springs are installed
in cars of the various model
years.
ModeN
Modell87
,&$& 45i!@-%
, ---.~~--
i
1 v
i
Toots (IMPROVISED)
Valve spring plate SP No.
944.105.467.03
Secondary spring SP No.
928.107.171.01
2.To facilitate installation
shorten secondary spring to
approx. 50 mm.
3.Install valve and press against
valve seat. Install plate, valve
spring retainer, secondary spring
and spring plate with ground
surface.
4.Install conical valve keepers
with Special Tool 9242.
Note:
When selecting the valve spring
plate (improvised) it is essential
to ensure that the valve spring
plate is 2.0 + 0.2 mn thick.
l.Grind a face approx. ID ann broad
on valve spring plate. Install
spring plate for measurement
only.
5.Using a depth gage, measure from
surface of valve spring plate
vertically through gap to outer
spring bearing surface.
a
15
- 116b Checking and Adjusting Installation
XVI,1987
- Printed in Germany
Length of Valve Springs