Valve Guides; Valves - Toro Groundsmaster 300 Series Service Manual

Valve Guides (Fig. 55)
If the valve guide clearance, after cleaning, exceeds the
specifications in step 6 above, they must be replaced.
1. Remove the existing valve guide by pressing it up-
ward using a valve guide removing mandrel with a pilot
section.
2. To install the new guide press it in from the top of the
cylinder head using the valve guide mandrel. Valve
guides should be installed so that their installed height
is as shown.
NOTE: Placing the valve guide in a refrigerator or
freezer for several minutes before installation will aid in
assembly.
3. After installing the valve guide, again check the guide
to stem clearance. If the clearance is smaller than the
standard size it will be necessary to ream the valve
guide bore to obtain the proper clearance.
Valves (Fig. 56)
1. Carefully clean each valve with a wire wheel to
remove all carbon deposits.
2. Check the valve face and the valve stem for excessive
wear, damage, cracks or deformation. If any of these
conditions exist the valve must be replaced. It is possi-
ble to reface the valve as long as the margin or valve lip
thickness is not less than the surface limit.
3. Check the tip of the valve stem for wear or pitting. If
pitted or worn the valve stem tip may be resurfaced by
placing the valve stem in a V-block and dressing the tip
against a grinding wheel.
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Groundsmaster 300 Series Page 4 - 49
Figure 55
Installing valve guide
Figure 56
Dimensions of valve
Cylinder Head Overhaul