Valve Guides
- Measure valve stem diameter. Replace valve if stem diameter is not within specification. Measure valve stem oil clearance. See CYLINDER HEAD and VALVES & VALVE SPRINGS tables under ENGINE SPECIFICATIONS.
- If clearance exceeds service limit, valve guide can be replaced with an oversized valve guide. See OVERSIZED VALVE GUIDE SPECIFICATIONS table.
- On Precis, remove valve guide from cylinder head, using Valve Guide Remover/Installer (09222-21200). On all other models, use commercial valve guide remover to remove valve guide. On all models, drive valve guide out toward combustion chamber side of cylinder head.
- Note intake valve guides are shorter than exhaust valve guides. Using valve guide installer, press new valve guide into cylinder head from top. Install valve guide to proper height. Measure guide clearance of new valve guides. Ream valve guide as necessary. Reface valves and seats. See CYLINDER HEAD and OVERSIZED VALVE GUIDE SPECIFICATIONS tables.
CAUTION:
DO NOT install valve guide with same diameter as that removed.
OVERSIZED VALVE GUIDE SPECIFICATIONS (1)
| Size Mark | Guide Size In. (mm) | Cylinder Head Bore In. (mm) | |||
|---|---|---|---|---|---|
| Precis | |||||
| 5 | .002 (.05) | .4766-.4770 (12.105-12.115) | |||
| 25 | .010 (.25) | .4844-.4848 (12.305-12.315) | |||
| 50 | .020 (.50) | .4943-.4947 (12.555-12.565) | |||
| All Others | |||||
| 5 | .002 (.05) | .4744-.4751 (12.050-12.070) | |||
| 25 | .010 (.25) | .4823-.4830 (12.250-12.270) | |||
| 50 | .020 (.50) | .4921-.4928 (12.500-12.520) | |||
|
|||||