Search results
Results from the WOW.Com Content Network
A valve job is the colloquial term for resurfacing the mating surfaces of the poppet valves and their respective valve seats that control the intake and exhaust of the air/fuel mixture in four stroke internal combustion engine, replacing valve oil seals, replacing any deficient valve springs, and otherwise bringing the components of a cylinder head up to manufacturer’s spec. [1] A ...
Lapping machine. Lapping is a machining process in which two surfaces are rubbed together with an abrasive between them, by hand movement or using a machine. Lapping often follows other subtractive processes with more aggressive material removal as a first step, such as milling and/or grinding. Lapping can take two forms.
Longevity, as demonstrated in early automotive applications of the Knight engine. Prior to the advent of leaded gasolines, poppet-valve engines typically required grinding of the valves and valve seats after 20,000 to 30,000 miles (32,000 to 48,000 km) of service. Sleeve valves did not suffer from the wear and recession caused by the repetitive ...
In an overhead valve engine the tappets (on right) are sandwiched between pushrods and the camshaft. In an internal combustion engine, a tappet (also called a 'valve lifter' or 'cam follower') [3] [4] [5] is the component which converts the rotation of the camshaft into vertical motion to open and close an intake or exhaust valve.
This graph shows the pressure taken from the valve end (blue line) and the runner entrance(red line) of an engine with a 7-inch (180 mm) port/runner and running at 4500 rpm. Highlighted are two waves, a suction wave and a valve closing wave, seen and the valve end and runner entrance showing the signal delay.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more
A schematic diagram of the centerless grinding process. Centerless grinding is a machining process that uses abrasive cutting to remove material from a workpiece. [1] Centerless grinding differs from centered grinding operations in that no spindle or fixture is used to locate and secure the workpiece; [2] the workpiece is secured between two rotary grinding wheels, and the speed of their ...
With traditional fixed valve timing, an engine will have a period of "valve overlap" at the end of the exhaust stroke, when both the intake and exhaust valves are open. The intake valve is opened before the exhaust gases have completely left the cylinder, and their considerable velocity assists in drawing in the fresh charge. Engine designers ...