Toro Workman 3000 Series Service Manual page 76

When engine is hot
Coolant temperature 80�C (176�F) or higher:
Hand vacuum Normal condition
pump p mp
Engine
4 kPa (30 mm Hg, No change
1.2 in. Hg) of
vacuum applied
20 kPa (150 mm Idling becomes
Hg, 6 in. Hg) of slightly unstable
vacuum applied
EGR Valve Inspection
1. Remove EGR valve and inspect for sticking, carbon
deposits, etc. Clean with a suitable solvent if necessary
so valve seats correctly.
2. Connect a hand vacuum pump to EGR valve.
3. Apply 67 kPa (500 mm Hg, 20 in. Hg) of vacuum and
check to make sure vacuum is maintained.
4. Apply a vacuum and check passage of air by blowing
through one side of EGR passage.
Vacuum
4 kPa (30 mm Hg, 1.2 in. Hg)
or less
2.0 kPa (150 mm Hg, 6 in. Hg)
or more
Installation
1. Use a new gasket and tighten to a torque of 9 Nm (0.9
kgm, 0.6 ft–lb).
Liquid Cooled Gas Engine
Vacuum
Vacuum is
maintained
Passage of air
Air is not blown out
Air is blown out
Page 3 – 38
Figure 57
Workman 3000/4000 Series