valves
valve springs must be replaced if they
are bent, not square, do not meet tension specifications
what causes valves to stick
gum accumulation
a _______ must be used on each valve to hold it firmly against the seat
valve spring
valve overlap is when both valves are
open
what pushes against the valve tappets to make them move
cam lobes
the camshaft opens and closes the
intake and exhaust valves
which is not a part of a valve system
ring
a machined hole in the block through which the valve stem passes in order to align the valve and ensure accurate raising and lowering in relation to the seat is called the
valve guide
what is another name for a valve tappet
valve lifter
when referring to a type of engine OHV stands for
overhead valve
the difference in the angle between the valve seat and the valve face is called
interference fit
what are the 3 main types of valve train configurations used in small gasoline engines
L-head, overhead valve, reed valve
What is used in an engine to control the flow of fluids
valves
in the _______ arrangement, the camshaft is located in the crankcase and the valves are located in the cylinder block directly above the camshaft lobes
L-head
the L-head engine is also known as the _________ arrangement
valve-in-block
valves that are used in a 4-stroke cycle engine to open and close the port openings are called
poppet valves
the valve _________ consists of all of the components that work together to transform the rotation of the crankshaft into the opening and closing of the valves
train
which of the following is not a type of valve failure
swollen
valves should be cleaned with a power wire brush and then
inspected for defects
in the ______ arrangement both the camshaft and the valve assemblies are installed in the cylinder
overhead cam
briggs and stratton recommends that valves be replaced when the margin measures less than
1/64
the thickness of the margin on a new brings and stratton valve is
1/32
_________ is a process where the valve face is rubbed against the valve seat using an abrasive compound in order to produce a particular type surface
lapping
why are the valves more important in a one-cylinder engine than in a multi-cylinder engine
if the valves fail in a multi-cylinder engine you only lose a portion of the power but if they fail in a one-cylinder you lose all power
in the ___________ arrangement, the camshaft is installed in the crankcase and the valves are installed in the cylinder head
overhead valve