Powerplant Chapter 02 Flashcards
Reciprocating Engine Operation, Instruments, Maintenance, and Overhaul
What indications are given in the event of a leaking or open primer while the engine is running?
The engine will not idle properly.
A cold cylinder is found when troubleshooting a running engine. What does this indicate?
No combustion in that cylinder.
When pulling a propeller through, a hissing sound is heard, indicating valve blow-by. What procedure should be performed next?
A compression check should be performed to identify to the faulty cylinder.
What is the purpose of performing a compression test?
To determine if the valves, pistons and rings are sealing properly.
When an engine is overhauled, how is its total time affected? When an engine is rebuilt, how is its operating history affected?
The total time on the engine must be continued and the time since major overhaul is entered into the engine log. If the manufacturer rebuilds the engine, it is granted zero-time status and is considered to have no previous operating history.
What inspections should be performed after a propeller strike without sudden stoppage?
- Inspect engine mounts, the crankcase, and the nose section for damage.
- Inspect the oil and oil filters/screens for metal particles.
- Inspect the crankshaft or driveshaft for cracks and misalignment.
Name some of the precautions that should be performed prior to engine removal.
Disconnect the battery, turn off the fuel valves, chock the wheels, and if necessary, install a tail stand.
When inspecting a piston, where are cracks most likely to be found?
In those areas that are highly stressed; usually the base of the piston bosses, inside at the junction of the bore and the walls, the ring lands.
What does it means if an engine part is within “serviceable limits”?
It means that the part is within the manufacturer’s limits and can be used in an engine (does not require replacement).
What tools or instruments are used to inspect a cylinder barrel for out-of-roundness?
A dial indicator or an inside micrometer is usually used to measure the top of the cylinder and at the skirt. A telescopic gauge and micrometer can also be used. Two readings should be taken 90# to each other.
How can a loose stud in an engine crankcase be repaired?
Remove the loose stud and inspect the hole for size and thread condition. It may be necessary to use an oversize stud or Heli-Coil insert.
What publication is used to check an engine for normal operation?
Manufacturer’s maintenance manual.
A weak cylinder is found during a compression check. What must be inspected?
Pressure is transmitted equally in all directions.
What purpose does an oil analysis serve?
Metal particles in the oil show normal and abnormal wear of the engine. This helps in evaluating the engines internal condition.
What inspection should be performed on an engine that has been in storage?
Perform an inspection to determine if there is any corrosion damage.
