Holding my right hand up, I am a newbie :) any help is greatly appreciated.a) Comparing the shape of the valve to a golf tee, what is the correct name for the thinnest section of the valve(the part of the golf tee that goes into the ground)b) What is the correct name for the widest section of the valve(the part of the golf tee that the ball is placed on.c) The cylinder that the valve moves up and down in, is it just called the valve cylinder?d) In the valve cylinder?, how does the widest part of the valve keeps things sealed. Does it use a ring(simmilar to pistons) or is it some type of gasket material or is it just zero clearance metal to metal.e) The section of the (valve cylinder?) that is above the seal point or basicaly where the valve spring and the thinnest part of the valve is, does oil flow through here?f) Do (valve cylinders?) generate enough heat to warrant the need for coolant?Newbie City, I know. Any help is GREATLY appreciated.TY
stem, surface, valve guide, o rings in some. some valve guides are plastic with no clearance. yes oil flow, yes water flows through the heads to cool vales and head.
a) The very end is the tip. Below that are grooves that the keepers lock into. This is actually the thinnest part. Below that is the rest of the stem. The general name for the largest part in total is the valve head. b) Surface sounds right. Hadn't really thought about it before. LOL c) Valve Guide. These can either be just a plain hole in the cylinder head material, or often they have bronze inserts. Plain Guides are often repaired by a process called knurling. d) Valves seal to the head by grinding each at the same angle, (usually 45 degrees) and then they are lapped which is where an abrasive compound is placed in between, and the valve is rotated. This matches the surfaces more closely yet. The parts that seal are called the valve face and the seat which is actually a separate part that is inserted into the head, and can be replaced. e) Oil is supplied to that general area, by either holes in pushrods that lubricate the rocker arm, or in the case of rockers mounted to a shaft, through the shaft. In the first case, oil is supplied by the hydraulic lifters. In the latter, the shaft pedestals are drilled for oil passages. In both cases, oil is present in the area, but is not applied directly to the valves. In fact, the job of the valve stem seal is to keep too much oil from getting in the guides. f) Usually the coolant flowing through the heads is enough to carry away the heat, although some hi-performance engines employ techniques such as hollow exhaust valves filled with sodium. Most normal valves are solid.
