K 2500 Truck 4WD V8-454 7.4L VIN J SFI (1997)
Valve Seat: Service and Repair
Reaming
The intake valve guides used in the engine are simply holes bored into the cylinder head. The exhaust valve guides are made of cast iron and they are
pressed into the cylinder head. The valve guides are not replaceable. If the valve stem-to-bore clearance as previously measured is excessive, the valve
guides should be reamed an a valve with an oversize stem installed. Oversize valves are available. Select a reamer that will provide a straight, clean bore
through the entire length of the valve guide.