1942 - 1947 Chevrolet Shop Manual



	*6-26*

	After the valves are removed, the valve stems and heads should be cleaned on a buffing wheel to remove all carbon and other foreign matter. The condition of the valves and valve stems can now be checked. Reseating Valve Seats in Cylinder Head Reconditioning the valve scats on modern high compression engines is very important, because the seating of the valves must be perfect for the engine to deliver the power and performance built into it. Another important factor is the cooling of the valve heads; good contact between each valve and its seat in the head is imperative to insure that the heat in the valve head will be properly carried away. We recommend the use of a grinder of the eccentric type for reconditioning valve seats in the cylinder head, the use of which will be described in the following paragraphs.	wheel will pass over the stud projecting through "A" and the grinder will be in position ready to


		Fig. 57—Dressing Valve Seat Grinder dress the wheel, Fig. 57. Set the diamond dressing tool at the proper angle. Turn on the switch and dress the grinding wheel. NOTE—Do not allow the grinding wheel to become glazed or loaded with metal as it will not grind freely or do accurate work in this condition.

	Fig. 56—Installing Expanding Pilot Before attempting to recondition any valve seat, clean all carbon thoroughly from the valve port, wipe seat with gasoline, cleaning it of any grease or foreign matter. Great care should be taken to clean the valve guide with a wire brush and make sure it is free from carbon and dirt. These precautions insure proper centering of the pilot in the guide. Install the expanding pilot in the valve guide. Using the special handling wrench, expand the pilot with the knurled knob on the top of the wrench. Fig. 56, and remove the handling wrench. Dressing the Grinding Wheel The grinding wheel should be dressed before starting any valve reconditioning job. Set the grinder over the two top pilots of the dresser stand. When the grinder is seated on these pilots, the
		Fig. 58—Setting Adjusting Rod