Great Wall service chassis and body Manual - part 21

TF-25

(b)

Normal gear grinding trace.

Transfer Box

 Washing, Checking, Up-Keeping and Exchanging (Checking)

Checking

1.

Common Checking process

Check all parts by visual check to see whether there is damage

or serious or uneven wear (parts needed be substituted by new

parts such as O-ring, oil seal and etc. shall be excluded).

Abandon the damaged or weary parts that will affect on their

performance. The check items are as follows:

 Burr: tips protruded from the material regionally

 Rag: broken small blocks or particles

 Crack: surface thread showing the material is partly or

completely separated.

 Excessive abrasion
Refer to the serious or obvious abra-

sion beyond of application limit.

 Reduction change
Material slip caused by the heavy

pressure on part of it.

 adhesive bonding
Granules of the soft metal are dis-

persed and bonded on the hard metal surface.

 Ditch trance: partial crack or trough that means the material

transfer instead of material loss.

 Pitting corrosion
Damages to the metal surface caused by

pressure, which are displayed due to color change caused

by heat generated by metal friction.

 Step wear
a weary step may be seen or felled between the

neighboring interface or between the non-touching face

due to the excessive wear.

 Uneven wear: Partially, unevenly distributed wear, which

includes holes, bright spots, uneven polishing or other

visual drawbacks.

2.

Gear or Chain sprocket tooth inspection

Check the gear and chain sprocket tooth according to the

following process:

(a)

Normal gear shaving trace.

normal gear shaving trace

normal gear grinding trace

TF-26

Transfer Box

 Washing, Checking, Up-Keeping and Exchanging (Checking)

(e)

Unacceptable side deflective contact area that must be

changed.

(f)

Acceptable side-deflective contact area

(g)

Unacceptable side deflective contact area that must be

changed.

(c)

Ideal engagement contact area

(d)

Acceptable side-deflective contact area

TF-27

Transfer Box

 Washing, Checking, Up-Keeping and Exchanging (Checking)

(h)

Acceptable contact area deflecting to the tooth top.

(i)

Unacceptable contact area deflecting to the tooth top,

which must be changed.

(j)

Acceptable contact area deflecting to tooth root.

(k)

Unacceptable contact area deflecting to tooth root, which

must be changed.

4.

Key tooth inspection

Check the broken or peeled spline teeth. The spline teeth may,

if only small part is peeled off, be repaired in the same way as

that for the gear teeth, and can be reused. In case the spline

tooth is broken, the spline must be abandoned. The contact

type of spline is not the same as that for gear; however, spline

that shows step sliding must be abandoned.

TF-28

Transfer Box

 Washing, Checking, Up-Keeping and Exchanging (Maintenance or Change of Gear or Chain Sprocket Gear)

Maintenance or Change of Gear or Chain

Sprocket Gear

1.

Maintenance principle

(a) Conduct the maintenance for the partial, small peel off

with the suitable manual high-speed grinding tool.

(b) Do not clear away the metal as can as possible when

grinding the matrix metal.

(c) All pointed angles and sides must be repaired as the slip-

pery contour line. Because the pointed angle or edges

may be peeled off again or developed into crack.

(d) Clear away the burr with the suitable grinding stone. Take

notice not to damage the matrix when clearing away the

projecting materials, and

(e) When substituting the non-repaired parts (such as

bearing), if the part is doubted in its re-application

capability, it must be changed.

2.

Cases for gear or chain sprocket maintenance or substi-

tuting

(a)

The gear, being peeled off at the two sides of tooth top in

contact face, may be repaired for reuse.

(b)

The gear, being peeled off at the central tooth top of

contact face, may be repaired for reuse.

(c)

The gear, being peeled off at one side of the non-contact

face, may be repaired for reuse.