Isuzu KB P190. Service manual - part 677

Engine Mechanical – V6 

Page 6A1–229 

 

3 

Measure the crankshaft thrust wall width (1) for wear 
using an inside micrometer and compare with the 
engine specifications, refer to 5 

Specifications.

4 

Measure the crankshaft thrust wall surface (2) for 
runout using a dial indicator, mounted to a magnetic 
stand and compare with the engine specifications, 
refer to 5 

Specifications. 

5 

If the crankshaft journals are damaged or worn 
beyond specifications, the crankshaft may be ground 
0.25 mm. There is only one size of oversized main 
bearings available for service. 

 

Figure 6A1 – 422 

6 

Inspect the crankshaft main journals (1) for undersize, 
using an outside micrometer (2). 

 

Figure 6A1 – 423 

7 

Inspect the crankpins (1) for undersize using an 
outside micrometer (2). 

8 

Compare your measurements with those listed in the 
engine specifications, refer to 5 

Specifications. 

If the crankpin journals are worn beyond the 
specifications, the crankshaft may be ground 0.25 
mm. Only one size of oversized connecting rod 
bearings available for service. 

 

Figure 6A1 – 424 

Engine Mechanical – V6 

Page 6A1–230 

 

9 

Measure the main bearing and crankpin journals for 
out-of-round using the following procedure: 

a 

Using an outside micrometer, measure the 
journal at the extreme front and rear locations 
on the journal. Call these points A and B. 

b 

Measure the journal in two new locations 
exactly 90 degrees from the first points. Call 
these points C and D. 

c 

Subtract A from C and B from D. The 
differences will indicate journal out-of-round. 

d 

The out-of-round should not exceed 0.004 mm 
maximum. 

e 

If the journals are worn beyond the 
specifications, the crankshaft may be ground 
0.25 mm. There is only one size of oversized 
crankshaft and connecting rod bearings 
available for service. 

10 

Measure the main bearing and crankpin journals 
for taper using the following procedure: 

a 

Using an outside micrometer, measure the 
journal at the extreme front (A) and rear (B) of 
the journal parallel to the crankshaft centreline.

b 

Subtract the smallest from the largest 
measurement. The result will be the journal 
taper. 

c 

If the main bearing journal taper exceeds 
0.004 mm, replace the crankshaft. 

d 

If the journals are worn beyond the 
specifications, the crankshaft may be ground 
0.25 mm. There is only one size of oversized 
crankshaft and connecting rod bearings 
available for service. 

Figure 6A1 – 425  

 

 

Reinstall 

Crankshaft Bearing Installation Procedure 

CAUTION

 

If the crankshaft bearings have been used in 
a running engine, replace them with new 
crankshaft bearings for reassembly. 

1 

Clean the crankcase crank bore with a lint-free cloth.

2 

Clean all the oil from the backside of new bearing 
halves. 

3 

Install the new upper crankshaft bearings into 
position. The thrust bearing (1) belongs in the number 
3 journal(2). Ensure the upper bearing insert contains 
the oil transfer hole and groove. Roll the bearing into 
position so the lock tang engages the crank slot. The 
bearing must fit flush with the upper crankcase. 

Figure 6A1 – 426 

Engine Mechanical – V6 

Page 6A1–231 

 

4 

Install the new lower crankshaft bearings (2) into 
position in the main bearing caps (1). The lower 
crankshaft bearings are identified by no grooves or 
holes. The bearings must fit flush with the crankshaft 
bearing caps. 

 

Figure 6A1 – 427 

Crankshaft Main Bearing Clearance Measurement 

1 

Place a length of fresh, room temperature plastic 
gauging material all the way across all the crankshaft 
bearing journals. 

2 

Install the crankshaft main bearing caps. 

3 

Loosely install the original inner main cap bolts (1). 

4 

Loosely install the original outer main cap bolts (2). 

Figure 6A1 – 428 

5 

Loosely install the original short/inner side main cap 
bolts. 

6 

Loosely install the original long/outer side main cap 
bolts (3). 

7 

Gently tap the crankshaft main bearing caps with a 
soft-faced hammer to help seat the caps. 

8 

Tighten the main caps bolts to the correct torque 
specification, and in the following sequence. 

Crankshaft main bearing cap inboard 
attaching bolt torque specification: 
 

Stage 1 .........................20.0 Nm 

 Stage 

2 .................................80° 

Crankshaft main bearing cap outboard 
attaching bolt torque specification: 
 

Stage 1 .........................15.0 Nm 

 Stage 

2 ...............................110° 

Crankshaft main bearing cap side 
attaching bolt torque specification: 
 

Stage 1 .........................30.0 Nm 

 Stage 

2 .................................60° 

Figure 6A1 – 429 

Engine Mechanical – V6 

Page 6A1–232 

 

N O T E  

Do not rotate the crankshaft. 

9 

Allow the assembly to sit for 2 minutes. 

10 

Remove the crankshaft bearing cap side bolts. 

11 

Remove the crankshaft bearing cap outer bolts (2). 

12 

Remove the crankshaft bearing cap inner bolts (1). 

13 

Install the crankshaft main bearing cap remover Tool 
No. J-41818 as previously described and remove the 
crankshaft bearing cap. 

14 

Repeat steps 10 to 13 for the remaining crankshaft 
bearing caps. 

Figure 6A1 – 430 

15 

Determine the crankshaft bearing clearance by 
comparing the width of the flattened plastic gauging 
material (1) at its widest point with the graduation on 
the gauging material scale (2). 

16 

Compare the measurements listed in the 
specifications, refer to 5 

Specifications. If the 

new bearings do not provide the correct crankshaft to 
bearing clearance, inspect the following: 

17 

Measure the crankshaft journals for the correct 
specified size and ensure new bearings are being 
installed. If the crankshaft journals are incorrectly 
sized, replace or regrind the crankshaft. Crankshaft 
machining is permitted and undersized bearings are 
available. 

18 

Measure the engine block crankshaft bearing bore 
diameter to ensure correct size. The engine block 
crankshaft bearing bore is not machineable and the 
block must be replaced if out of specification. 

19 

Clean the plastic gauging material from the crankshaft 
bearing journals with a soft, lint-free cloth. 

Figure 6A1 – 431