© 2018 Avco Corporation. All Rights Reserved
System Description
October 2018
Page 13
TEO-540-A1A Engine Installation and Operation Manual
2.
Oil from the oil pump flows out through a threaded port on the accessory housing to a
flexible line to the external oil cooler.
3.
An oil cooler bypass valve in the engine accessory housing is installed to allow oil from the
pump to bypass the oil cooler circuit. This valve is fully closed when the oil temperature
reaches a set limit (identified in Appendix A) forcing all oil to flow through the oil cooler.
4.
From the oil cooler, pressurized oil flows back to the engine to a threaded port on the right
side of the accessory housing.
5.
The oil flows through a spin-on oil filter attached to the accessory housing and back into the
accessory housing (where the oil temperature and pressure are measured by sensors).
6.
The filtered oil flows through a drilled opening to the oil pressure relief valve on the upper
right side of the crankcase (in front of the accessory housing).
7.
The filtered pressurized oil flows to the camshaft and valve gear openings of the main oil
galley.
8.
Oil flows through branch openings to the roller tappets and camshaft bearings.
9.
Oil flows into the tappet through indexing holes and through the hollow push rods to the
valve mechanism. The oil lubricates the valve rocker bearings and valve stems.
10.
Oil continues to flow through isolated drilled openings to the main bearings of the crankshaft.
Angular holes go through the main bearings to the rod journals.
11.
Oil flows through the accessory housing to supply oil to all accessory housing-mounted
components.
12.
Oil also flows out of a threaded port in the accessory housing through external lines to the
turbochargers. Oil drains out of each turbocharger into a drain tank. The oil scavenge pump
sends oil back to the oil sump from the turbocharger oil drain tanks.
13.
Passages from the rear main bearings supply pressurized oil to both crankcase idler gears.
14.
Gravity drains oil from the bearings, accessory drives, and rocker boxes to the oil sump.
15.
The relief valve also sends oil back to the oil sump.
16.
The electronic oil temperature sensor sends temperature readings to the aircraft through the
communication bus.
17.
An electronic oil pressure sensor sends the oil pressure reading to the aircraft through the
communication bus.
Engine Mounting
Four brackets are supplied for rear Dynafocal mounting. Vibration isolators are not supplied. Refer
to the airframe manufacturer’s maintenance manual for details.
