TRUCK SERVICE MANUAL
3. Apply 75 to 100 ft-lbs [10.4 to 13.8 kg ml on puller
1. Check for cracks in cylinder liners just under top
flange, at bottom of liner, or above top seal ring groove as
4. Heat gear with heating torch not a cutting torch to 300
deg. to 400 °F [150° to 205 °C] .,The gear will expand,
a. Magnetic Method.
making it easier to pull. Remove gear key.
b. Dye Penetrants.
5. Inspect crankshaft visually for scratches, nicks, cracks
2. Discard any liner with excessive corrosion or erosion
and obvious wear pattern and measure crankshaft journals
and pits 1/16 inch [1.59 mm] deep or more or if dents, pitting
or fretting on underside of liner flange cannot be removed by
crankshaft for out-of-round condition.
Crankshafts should be reground if main bearing or crankpin
3. Check worn liners with dial bore gauge. Replace if
journals are worn out-of-round more than 0.002 inch [0.05 mm]
worn more than Worn Limit as shown in Table 1-1 (5).
4. Deglaze cylinder liner walls.
1. Remove all pipe plugs, clean all drilled oil passages in
crankshaft with a rod and rag as if cleaning a rifle barrel.
1. After liners are deglazed, they must be cleaned
2. Lubricate threads with clean SAE 20W or 30W
thoroughly with solvent, steam cleaner or hot soap and water.
lubricating oil, install and tighten plugs to 60 to 96 inch-lb [0.7
It is recommended that cleaning operation be ended by
scrubbing bore with a bristle brush to remove as much debris
as possible. Blow liners dry with compressed air. Coat bore
INSPECT CRANKSHAFT JOURNALS AND THRUST FLANGE
of liners generously with clean lubricating oil. If possible, let
1. Carefully examine crankshaft journals and thrust
liners stand 5 or 10 minutes. Use white paper towels to wipe
flange at No. 7 main bearing. If surfaces are scored or
lubricating oil from liner bores. Note gray and even black
scratched, crankshaft should be reground and undersize rod
residue that appears with oil on white towels.
and main bearings or oversize thrust rings installed.
application of lubricating oil and wipe off with white paper
2. Reground crankshafts or those used with undersize
rod · ,and main bearings and/or oversized thrust rings should
2. All new cylinder liners should be "prebrushed" and
be marked so correct bearing shells and thrust rings can be
cleaned before assembly to assure no abrasives are present
installed in proper position. Fig's. 1-3 and 1-4.
in the Lubrite coating.
3. The marking for undersize rod and main bearings
should be on front counterweight, oversize thrust ring size on
rear counterweight. Both thrust ring size and ring location
Crankshafts are steel forgings with accurately machined and
must be included in stamping as shown in Fig. 1-4.
hardened main and connecting rod journals. Each shaft is
For example: Front 0.
inch [0.25 mm] and rear 0.020 inch
balanced for proper weight distribution to insure even forces
DISASSEMBLY AND INSPECTION
Install crankshaft gear, if removed.
1. If crankshaft gear is chipped, cracked, broken or worn;
Note: Check parts catalog for correct gear part number.
remove lockplate and nut (if used).
a. Install key or dowel pin in shaft.
b. Heat gear in a pre-heated oven at 450 deg. F [214
If crankshaft gear condition is satisfactory, do not
deg. C] for a minimum of one hour.
2. Attach a circular-type puller behind the crankshaft