TM 10-4320-307-24
4-8
TURBOCHARGER (T18-A) REPAIR (CONT).
6.
Place parts carefully in a clean basket to avoid damage or dirt.
7.
Inspect compressor impeller for the following:
a.
Signs of rubbing
b.
Damage from foreign material
c.
Signs of burning in bore area
d.
Signs of seals rubbing the running surfaces.
8.
Inspect compressor housing for the following:
a.
Scoring due to contact with compressor impeller. If small scratches or chips are found they can be smoothed out
with crocus cloth.
b.
Cracks or distortion. Discard housing if cracked or distorted.
9.
Inspect turbine wheel and shaft for following:
a.
Signs of rubbing
b.
Vane edges worn to fine edge
c.
Scoring or scratches on shaft
d.
Seized bearings
e.
Cracks in turbine wheel. Check with dry penetrant.
f.
Scoring of turbine thrust shoulder.
10. Measure shaft bearing journal diameters. Replace wheel and shaft assembly if journal diameters are worn below
0.6245 inch (15.862 mm).
11. Inspect turbine housing for the following:
a.
Scoring due to contact with rotating parts
b.
Cracks or distortion. Discard housing if cracked or distorted.
c.
Cracking, distortion, or signs of burning at mounting flange.
12. Inspect center housing (or bearing housing) for cracks, pitting, and distortion. Pay particular attention to inlet and
outlet ports of oil passages. Discard center housing if damaged.
13. Measure center housing (or bearing housing) bearing bores. Replace center housing if bore diameter exceeds
0.9835 inch (24.981 mm).
14. Inspect backplate for pitting, cracks, or distortion. Check vanes for chipping, wear, or corrosion. Replace backplate
if damaged.
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