Use a hot plate or oven to evenly heat the cylinder head to 150 °C (300 °F). Monitor the temperature with a cooking thermometer. Do not get the head hotter than 150 °C (300 °F); excessive heat may loosen the valve seats. Working from the camshaft side, use the driver and an air hammer to drive the guide about 2 mm (0.1 in.) towards the combustion chamber. This will knock off some of the carbon and make removal easier. Hold the air hammer directly in line with the valve guide to prevent damaging the driver. Wear safety goggles or a face shield. |