PREVENTIVE MEASURES

TM 10-3930-644-14&P

2. Remove the excess carbon deposits from the

F. PREVENTIVE MEASURES

top of the cylinder wall before beginning the

glaze breaking operation. This prevents loading

When cylinders and pistons are scored or worn

the stones.

excessively, the following most common causes should

be considered, in order to eliminate those conditions

3. Insert none in cylinder and expand to cylinder

during future operation of the engine.

wall with slight tension. Using a clean brush,

wet cylinder wall and stones with kerosene. Use

1. Gum or Varnish Deposits:

a hand drill and surface hone cylinder with a

rapid up and down motion to produce a good

Use heavy duty lubricating oil, change the oil

cross hatch pattern (Figure 11-4).

Apply

more often or reduce the oil temperature.

kerosene occasionally as needed and increase

tension on hone adjustment until a good pattern

2. Piston Skirt Clearance Inadequate:

and finish are obtained. A smooth finish of 10 to

15 micro Inches is desired.

When

fitting

new

pistons,

the

recommendations listed in TOPIC 1. FITS AND

4. Clean the loose abrasives from the stones by

TOLERANCES.

using kerosene and a wire brush.

3. Insufficient Cooling:

NOTE

Thoroughly clean the cooling system, check the

Stones must be used wet.

Keep

thermostat and water pump. Make sure hoses

applying kerosene during honing to

have not collapsed.

prevent stones from drying out and

causing an incorrect honing pattern.

4. Dirt Entering Intake Manifold:

5. The most desirable cylinder finish is 10-15 micro

inches; with this finish the depressions in the

Adopt

improved

air

cleaner

servicing

surface tend to keep the supply of lubrication

procedures.

Make sure the air cleaner

between the mating parts. This finish can be

connections are tight.

obtained by using 280 grit stones on the hone.

G. INSTALLATION

6. Clean all bores thoroughly with a clean oiled rag

to pick up all the small particles of dust that may

(Refer

TOPIC

17,

ENGINE

REMOVAL/

be embedded in the walls. Follow this with a

INSTALLATION.)

clean cloth to make certain the walls are

CLEAN.

R-104-1

3-42