190 / 1525
45
486 PL ENGINE
P
Fig. 102
Fig. 101
Fig. 100
Installation :
Place valve seat insert in a mixture of methanol
and dry ice for about 20-30 min. to bring its
temperature down to -50
0
C.
Heat cylinder head to approx. 80
0
C in water bath.
CAUTION :
The cylinder head should not be locally heated.
Install valve seat insert in cylinder head bore quickly
by slightly hammering. Fig. 100 & 101
Machine valve seat in cylinder head.
Checking of valve seating :
Smear valve seat with carbon blue, install valve in
guide and turn it slowly under axial pressure.
The contact line on valve seat must be around entire
circumference at equal width.
Check for leakages through valve seat by pouring
gasoline on valve head. Gasoline must not seep
past valve seat. Fig. 102
(Cylinder head with valves is in inverted condition).