Lycoming YO-233-B2A - Page 88

TEO-540-A1A Engine Maintenance Manual
12-10 © 2021 Avco Corporation. All Rights Reserved
Page 68 February 2021
YO-233-B2A Engine Maintenance Manual
Table 3 (Continued)
Guidelines for Identification of Metal Particulates and Chips & Corrective Action
Metals/
Alloys
Tests & Characteristics
Possible Source of
Origin on Lycoming
Engine
Next Step
Chrome
Piston rings
Exhaust valve stems
Refer to Table 4 for
the quantity and size
of the particles
Copper
When placed in nitric
acid, turns bright green
Platings
Refer to Table 4 for
the quantity and size
of the particles
Brass
When placed in nitric
acid, turns bright green
Oil suction screen
Pressure relief valve
spacer
Refer to Table 4 for
the quantity and size
of the particles
Lead
Bearings
If lead chips, chunks,
or balls are found,
complete Corrective
Action 4 in Table 5.
Aluminum
flakes
When placed in 50%
solution of nitric acid and
muriatic acid
(approximately 30%
hydrochloric acid and
water), or a sodium
hydroxide solution, the
aluminum particles bubble
and fizz and form a black
residue
Crankcase
Accessory housing
Oil pump body
Cylinder head
Pistons
Piston pin plugs
Oil sump baffle
Turbocharger inlet
housing
Sleeve bearings
Refer to Table 4 for
the quantity and size
of the particles
Magnesium
Oil sump
Refer to Table 4 for
the quantity and size
of the particles
Tin
Soft, malleable
Not picked up by magnet
When dropped onto a hot
(500◦F) soldering iron, tin
particle will melt and fuse
with 50/50 solder
Tin-plated parts
Refer to Table 4 for
the quantity and size
of the particles
Cadmium
Plating
Refer to Table 4 for
the quantity and size
of the particles
Zinc
Plating
Refer to Table 4 for
the quantity and size
of the particles