Volvo Penta TD520GE Workshop Manual page 89

Group 21
9. Measure the distance between the center of the
valve head and the cylinder head mating surface.
Depth of valve in cylinder head:
Measurement between valve disc and cylinder
head face:
Inlet/Exhaust ...................... Max 1.5 mm (0.06")
10. Measure the length of the valve spring using a
sliding caliper and with the spring unloaded.
Unloaded length, standard
64.70 ±1.3 mm (2.55" ±0.05")
11. Use the grinding tool to grind the valves into their
seats and correct the seat angle.
Valve seat angle Inlet
30°
Valve seat width, maximum
Inlet
2.8 mm (011") 2.2 mm (0.09")
NOTE! Measure the depth of the valve in the cylinder-
head again after you have ground in the valves.
12. Insert the valve steam seal (1)
13. Fit the valves, valve springs and spring discs.
NOTE! Oil the stems of the inlet and exhaust
valves. Push the valves in gently, with a slight
twisting motion. The o-ring (1) is very thin and can
easily be damaged.
14. Use valve spring compressor 998 5468 for the
valve springs. Insert the valve retainers.
Checks and adjustments
Exhaust
45°
Exhaust
99