Valve: Testing and Inspection

INSPECTION
1. Clean valves thoroughly and discard burned, warped and cracked valves.
2. Measure valve stems for wear. Refer to specifications. Valve stems are chrome plated and should not be polished.
3. Remove carbon and varnish deposits from inside of valve guides with a reliable guide cleaner.
4. Measure valve stem guide clearance as follows:
a. Install valve into cylinder head so it is 14 mm (0.551 inch) off the valve seat. A small piece of hose may be used to hold valve in place.





b. Attach dial indicator Tool C-3339, or equivalent to cylinder head and set it at right angle of valve stem being measured.
5. Move valve to and from the indicator. Refer to specifications.
6. Ream the guides for valves with oversized stems if dial indicator reading is excessive or if the stems are scuffed or scored.
7. Service valves with oversize stems and over size seals are available in 0.16 mm (0.005 inch), 0.40 mm, (0.015 inch) and 0.80 mm (0.030 inch) oversize.

NOTE: Oversize seals must be used with oversize valves.

8. Reamers to accommodate the oversize valve stem are shown.
9. Slowly turn reamer by hand and clean guide thoroughly before installing new valve. Do not attempt to ream the valve guides from standard directly to 0.80 mm (0.030 inch) Use step procedure of 0.15 mm (0.005 inch), 0.40 mm (0.015 inch) and 0.80 mm (0.030 inch) so valve guides may be reamed true in relation to the valve seat. After reaming guides, the seat runout should be measured and resurfaced if necessary.

NOTE: Replace cylinder head if guide does not clean up with 0.80 mm (0.030 inch) oversize reamer, or if guide is loose in cylinder head.