Valve Guide Replacement

REPLACEMENT





1. As illustrated, use a commercially available air-impact valve guide driver attachment modified to fit the diameter of the valve guides. In most cases, the same procedure can be done using the special tool and a conventional hammer.
2. Select the proper replacement guides and chill them in the freezer section of a refrigerator for about an hour.





3. Use a hot plate or oven to evenly heat the cylinder head to 300°F (150°C). Monitor the temperature with a cooking thermometer.

CAUTION:
- Do not use a torch; it may warp the head.
- Do not get the head hotter than 300°F (150°C); excessive heat may loosen the valve seats.
- To avoid burns, use heavy gloves when handling the heated cylinder head.

4. Working from the camshaft side, use the driver and an air hammer to drive the guide about 2 mm (0.1 inch) towards the combustion chamber. This will knock off some of the carbon and make removal easier.

CAUTION:
- Always wear safety goggles or a face shield when driving valve guides.
- Hold the air hammer directly in line with the valve guide to prevent damaging the driver.





5. Turn the head over and drive the guide out toward the camshaft side of the head.

If a valve guide still won't move, drill it out with a 8 mm (5/16 inch) bit, then try again.

CAUTION: Drill guides only in extreme cases: you could damage the cylinder head if the guide breaks.

6. Remove the new guides from the freezer, one at a time, as you need them.








7. Apply a thin coat of clean engine oil to the outside of the new valve guide. Install the guide from the camshaft side of the head; use the special tool to drive the guide in to the specified installed height. If you have all 12 guides to do, you may have to reheat the head.

Valve Guide Installed Height:
Intake: 15.75 - 16.25 mm (0.620 - 0.640 inch)
Exhaust: 15.75 - 16.25 mm (0.620 - 0.640 inch)

REAMING

NOTE: For new valve guides only.

1. Coat both the reamer and valve guide with cutting oil.





2. Rotate the reamer clockwise the full length of the valve guide bore.
3. Continue to rotate the reamer clockwise while removing it from the bore.
4. Thoroughly wash the guide in detergent and water to remove any cutting residue.
5. Check the clearance with a valve. Verify that the valve slides in the valve guide without exerting pressure.