Volvo B27A - Page 52

Group 21 Reconditioning engine
Cylinder head, reconditioning
E19
Place new valve seat in correct assembly tool
Use 5029 for intake seats and 5220 for exhaust seats.
E20
Cool valve seat to -70°C (-95°F)
Use liquid carbon dioxide or equivalent.
Wear protective gloves and safety glasses.
E21
Tap in valve seat
Note! This must be done quickly, within 3-4 seconds to
avoid temperature loss.
E22
Check fit of valve seat
Make sure that the seat has bottomed correctly and is
secure. If not, fit a larger size.
After valve seat replacement, valve seats must be milled
and valves ground.
<l
1.7-2.1 mm
(0.0669-0.0826 in)
Intake valve seat
Early types
30
Grinding of valves and valve seats
Operations E23-24
Machine grind valves
Intake valves 29.5°
Exhaust valves 44.5°
Also grind flush the end of the valve stem.
Mill or grind valve seats
Check valve fit
If necessary grind-in valves with grinding paste.
E23
E24
A
1.3-1.7 mm
(0.0511-0.0669 in)
Intake valve seat
Late types (venturi seat):
15° and 60° are correct angles
to reduce seat width.
2.0-2.4 mm
(0.0787-0.0944 in)
Exhaust valve seat
50