when performing a valve lash adjustment on a diesel engine, which of the following is recommended?
engine stationary and cold
.
What is the recommended tool used to check valve lash dimensions?
Feeler gauges
are the most convenient way to measure small clearances such as valve lash, connecting rod side clearance, or piston ring gap.
Which component is usually adjusted to adjust the valve timing?
Camshaft
. In four-stroke cycle engines and some two-stroke cycle engines, the valve timing is controlled by the camshaft. It can be varied by modifying the camshaft, or it can be varied during engine operation by variable valve timing.
Which of the following tools should be used to measure valve clearance with solid valve lifters?
Valve stem-to-guide clearance should be measured using a:
dial indicator or micrometer and ball gauge
. To begin cylinder head component reassembly, Technician A says valve stems should be coated with clean engine oil or engine assembly lubricant before installing the valves.
What material is used in the manufacture of most commercial diesel engine cylinder blocks today?
| Which of the following cylinder block designs would be the most common in medium and heavy duty truck diesel engines? Inline six cylinder | Most current heavy duty, diesel engine cylinder blocks are manufactured from: Compacted graphite iron (CGI) |
|---|
How much does a valve adjustment cost?
The average cost for a valve adjustment is
between $246 and $336
. Labor costs are estimated between $220 and $278 while parts are priced between $26 and $58. Estimate does not include taxes and fees.
What is valve lash adjustment?
What is a valve adjustment? The valve mechanism (push rod, lifter, and rocker arm assembly)
is adjusted so that the lash has the proper clearance necessary to regulate the opening and closing of the valve
. If the lash clearance is too great, it will affect the engine’s airflow and will eventually lead to valve damage.
What happens when valves are out of adjustment?
Too much or too little valve clearance can result in poor performance or a rough idle because the engine can’t “breathe” normally and operate at peak efficiency. Too much clearance means the valves will likely clatter and, over the long term,
cause damage to the valves
, camshaft lobes or rocker arms.
When should valve clearance be adjusted?
The clearance is correct
when the gauge is a close sliding fit between the two parts
. If the clearance is wrong, either the blade cannot enter the gap or it is loose, so that you can move the rocker up and down with the blade in place.
What happens when valves are to tight?
Tighter valves will not make any new noise. When the intake valves get
too tight they will cause hard starting and poor idling
. When the exhaust valves get too tight they will also cause hard starting and eventually get hot enough to start melting – not pretty.
What are the two types of method used on valve adjustment?
Common inspection and adjustment of valve clearance There are two methods: First, each
cylinder Adjustment Act
, which is the ignition cylinder priorities identified in a piston cylinder compression only on the location, this can be-cylinder, exhaust valve clearance adjustments; After shaking properly transferred to the …
What are the tools needed in adjusting valve clearance?
All except a hydraulic system will require a
feeler gauge
. The hydraulic lifter system will require the correct size socket and ratchet. The solid tappet will require feeler gauges, the correct size wrench, and a flat head screwdriver.
How do you tell if tappets need adjusting?
Read the measurement on the feeler gauge for a description of the clearance. If you are trying to set a gap of 0.102mm (0.004′′), for example, begin with this gauge.
If the gauge will not go in
, the tappet will require adjusting.
What are the three basic piston types used in diesel engines?
There are three basic size groups of diesel engines based on power—
small, medium, and large
.
Which type of oil pump is most commonly used in current highway diesel engines?
Positive displacement pumps of the external gear and gerotor types
are used as oil pumps in diesel engines; most are of the external gear pump design.
What is the most common method of surface hardening the journals on a heavy duty crankshaft?
INDUCTION HEAT TREATMENT
is a common method for hardening and tempering of crankshafts, which are necessary component in most every internal combustion engine (ICE) for cars, trucks, and machinery, as well as pumps, compressors, and other devices.
