DISTRIBUTOR TIMING.

TM 10-3930-623-34

NOTE

7-35. DISTRIBUTOR ADVANCE MECHANISM TEST.

Install assembled distributor in standard shop distributor

tester and test that automatic advance mechanism

During operation the point contact

meets specifications in Section II.

will develop a rough surface or

transfer of material from the movable

contact to the stationary contact.

NOTE

This is normal and replacement is not

necessary until buildup exceeds

The rpm's listed in the specifications

0.020 inch. Do not remove buildup

refer to the distributor speed and not

with point file as this reduces contact

the engine crankshaft speed. The

area.

distributor driven by the camshaft

rotates at half the engine speed.

9. Examine cam (32) lobes for excessive wear and

7-36.

DISTRIBUTOR TIMING.

grooving. Replace cam if lobes are damaged.

Refer to TM 10-3930-623-12.

10. Inspect housing (39) for cracks or distortion.

Discard defective or damaged housing.

7-33.

DISTRIBUTOR

CONTACT

POINT

GAP

ADJUSTMENT.

Refer to TM 10-3930-623-12.

7-37. ENGINE ASSEMBLY INSPECTIONS.

7-38. CYLINDER BLOCK INSPECTION.

Inspect as

follows:

1. Check cylinder head (52, figure 4-22) machined

surface with a straight edge and feeler gage for flatness

in three positions lengthwise and five crosswise.

Maximum deviation permitted is 0.004 inch low in center

lengthwise and 0.003 inch crosswise. Minor variations

up to 0.010 inch can be repaired by surface grinding or

milling (but not hand filing). Discard heads showing

7-34.

DISTRIBUTOR CONTACT SPRING

greater warpage.

TENSION TEST.

Refer to TM 10-3930-623-12.

2. Check top surface of cylinder block (62) to same

standards, disregarding possible raised areas around

screw holes.

3. Inspect block casting for cracks, loose or

defective plugs.

4. Inspect cylinder bores in block for taper from top

to bottom, out-of-round using an inside micrometer or

cylinder gage, (28, figure 7-1), or for any scores or

scratches in the walls. Taper exceeding 0.008 inch, out-

of-round exceeding 0.003 inch or scratches that cannot

be removed by honing require reboring of all cylinders

(even if only one is defective) to the next standard

oversize bore that will correct the condition. Reboring

requires installation of correct oversized pistons and

rings regardless of the serviceability of the removed

units.

7-13