GSIC - Global Service Information Center

# ENGINE UNIT > INSPECTION

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1. INSPECT BACKLASH OF OIL PUMP GEAR TO CRANKSHAFT TIMING GEAR

1. Using a dial indicator, measure the backlash.

   Standard gear backlash:
     0.02 to 0.15 mm (0.0008 to 0.0060 in.)

   Maximum gear backlash:
     0.20 mm (0.0079 in.)
   If the gear backlash is greater than the maximum, replace the gears as a set.

2. INSPECT NO. 1 IDLE GEAR THRUST CLEARANCE

1. Using a dial indicator, measure the thrust clearance.

   Standard thrust clearance:
     0.06 to 0.11 mm (0.0024 to 0.0043 in.)

   Maximum thrust clearance:
     0.30 mm (0.0118 in.)
   If the thrust clearance is greater than the maximum, replace the thrust plate. If necessary, replace the idle gear and/or idle gear shaft.

3. INSPECT BACKLASH OF CRANKSHAFT TIMING GEAR TO NO. 1 IDLE GEAR

1. Install the idle gear.

1. Using a dial indicator, measure the backlash.

   Standard gear backlash:
     0.02 to 0.15 mm (0.0008 to 0.0060 in.)

   Maximum gear backlash:
     0.20 mm (0.0079 in.)
   If the gear backlash is greater than the maximum, replace the gears as a set.

1. Remove the idle gear.

4. INSPECT BACKLASH OF OIL PUMP GEAR TO NO. 1 BALANCE SHAFT

1. Using a dial indicator, measure the backlash.

   Standard gear backlash:
     0.02 to 0.15 mm (0.0008 to 0.0060 in.)

   Maximum gear backlash:
     0.20 mm (0.0079 in.)
   If the gear backlash is greater than the maximum, replace the gears as a set.

5. INSPECT BACKLASH OF SUPPLY PUMP GEAR TO NO. 2 BALANCE SHAFT

1. Install the supply pump with the 2 nuts.

   Torque:
     21 N*m{ 214 kgf*cm , 15 in.*lbf }

1. Using SST, install the supply pump gear with the nut.

   SST
     09960-10010 (09962-01000, 09963-01000)

   Torque:
     64 N*m{ 652 kgf*cm , 47 in.*lbf }

1. Using a dial indicator, measure the backlash.

   Standard gear backlash:
     0.02 to 0.15 mm (0.0008 to 0.0060 in.)

   Maximum gear backlash:
     0.20 mm (0.0079 in.)
   If the gear backlash is greater than the maximum, replace the gears as a set.

6. INSPECT BACKLASH OF SUPPLY PUMP GEAR TO NO. 1 IDLE GEAR

1. Install the idle gear without sub gears.

1. Using a dial indicator, measure the backlash.

   Standard gear backlash:
     0.02 to 0.15 mm (0.0008 to 0.0060 in.)

   Maximum gear backlash:
     0.20 mm (0.0079 in.)
   If the gear backlash is greater than the maximum, replace the gears as a set.

1. Using SST, remove the nut and supply pump gear.

   SST
     09960-10010 (09962-01000, 09963-01000)

1. Remove the 2 nuts and supply pump.

1. Remove the idle gear.

7. INSPECT NO. 1 IDLE GEAR OIL CLEARANCE

1. Using a cylinder gauge, measure the inside diameter of the idle gear.

   Idle gear inside diameter:
     44.000 to 44.025 mm (1.7323 to 1.7333 in.)

1. Using a micrometer, measure the diameter of the idle gear shaft.

   Idler gear shaft diameter:
     43.955 to 43.990 mm (1.7305 to 1.7319 in.)

1. Subtract the idle gear shaft diameter measurement from the idle gear inside diameter measurement.

   Standard oil clearance:
     0.010 to 0.070 mm (0.0004 to 0.0028 in.)

   Maximum oil clearance:
     0.20 mm (0.0079 in.)
   If the clearance is greater than the maximum, replace the gear and shaft.

8. INSPECT NO. 1 BALANCE SHAFT SUB-ASSEMBLY

1. Using a dial indicator, measure the thrust clearance by moving the balances shaft back and forth.

   Standard thrust clearance:
     0.065 to 0.140 mm (0.0026 to 0.0055 in.)

   Maximum thrust clearance:
     0.25 mm (0.0098 in.)
   If the thrust clearance is greater than the maximum, replace the balance shaft thrust washer.

   HINT:
     After replacement, if the thrust clearance is still greater than the maximum, replace the balance shaft.

9. INSPECT NO. 2 BALANCE SHAFT SUB-ASSEMBLY

1. Using a dial indicator, measure the thrust clearance by moving the balance shaft back and forth.

   Standard thrust clearance:
     0.065 to 0.140 mm (0.0026 to 0.0055 in.)

   Maximum thrust clearance:
     0.25 mm (0.0098 in.)
   If the thrust clearance is greater than the maximum, replace the balance shaft thrust washer.

   HINT:
     After replacement, if the thrust clearance is still greater than the maximum, replace the balance shaft.

10. INSPECT CYLINDER HEAD SET BOLT

1. Using a vernier caliper, measure the minimum outside diameter of the compressed thread at the measuring point A.

   Standard outside diameter:
     11.8 to 12.0 mm (0.465 to 0.472 in.)

   Minimum outside diameter:
     11.6 mm (0.457 in.)
   If the outside diameter is less than the minimum, replace the bolt.

11. INSPECT SUPPLY PUMP GEAR BEARING

1. Check that bearing is not rough or worn.
   If necessary, replace the bearing.

12. INSPECT CYLINDER BLOCK OIL ORIFICE

1. Check the oil orifice for damage or clogging.
   If necessary, replace the oil orifice.

13. INSPECT CONNECTING ROD THRUST CLEARANCE

1. Using a dial indicator, measure the thrust clearance while moving the connecting rod back and forth.

   Standard thrust clearance:
     0.100 to 0.300 mm (0.0039 to 0.0118 in.)

   Maximum thrust clearance:
     0.40 mm (0.0157 in.)
   If the thrust clearance is greater than the maximum, replace the connecting rod assembly. If necessary, replace the crankshaft.

14. INSPECT CONNECTING ROD OIL CLEARANCE

1. Clean the crank pin and bearing.

1. Check the crank pin and bearing for pitting and scratches.
   If the crank pin or bearing is damaged, replace the bearings. If necessary, grind or replace the crankshaft.

1. Lay a strip of Plastigage across the crank pin.

1. Install the connecting rod cap with the 2 bolts.

   NOTICE:
     Do not turn the crankshaft.

1. Check the matchmarks on the connecting rod and cap to ensure correct reassembly.

1. Remove the 2 bolts, connecting rod cap and lower bearing.

1. Measure the Plastigage at its widest point.

   Standard oil clearance:

     STD | U/S 0.25, U/S 0.50
     0.036 to 0.054 mm (0.0014 to 0.0021 in.) | 0.037 to 0.077 mm (0.0015 to 0.0030 in.)

   Maximum oil clearance:
     0.10 mm (0.0039 in.)
   If the oil clearance is greater than the maximum, replace the bearings. If necessary, grind or replace the crankshaft.

   HINT:
     If using a standard bearing, replace it with one that has the same number. If the number of the bearing cannot be determined, select the correct bearing by adding together the numbers imprinted on the crankshaft and connecting rod, then selecting the bearing with the same number as the total. There are 5 sizes of standard bearings, marked 2, 3, 4, 5 and 6.

   Bearing size:

     Item | Number Mark
     Connecting rod cap | 1 | 2 | 3
     Crankshaft | 1 | 2 | 3 | 1 | 2 | 3 | 1 | 2 | 3
     Use bearing | 2 | 3 | 4 | 3 | 4 | 5 | 4 | 5 | 6

   EXAMPLE:
   Connecting rod cap "3" + Crankshaft "1" =
   Total number 4 (Use bearing "4")

   Reference:
     Connecting rod big end inner diameter:

     Mark | Diameter
     1 | 62.014 to 62.020 mm (2.4415 to 2.4417 in.)
     2 | 62.020 to 62.026 mm (2.4417 to 2.4420 in.)
     3 | 62.026 to 62.032 mm (2.4420 to 2.4422 in.)

     Crankshaft pin diameter:

     Mark | Diameter
     1 | 58.994 to 59.000 mm (2.3226 to 2.3228 in.)
     2 | 58.988 to 58.994 mm (2.3224 to 2.3226 in.)
     3 | 58.982 to 58.988 mm (2.3221 to 2.3224 in.)

     Standard sized bearing center wall thickness:

     Mark | Diameter
     1 | 1.486 to 1.489 mm (0.0585 to 0.0586 in.)
     2 | 1.489 to 1.492 mm (0.0586 to 0.0587 in.)
     3 | 1.492 to 1.495 mm (0.0587 to 0.0589 in.)
     4 | 1.495 to 1.498 mm (0.0589 to 0.0590 in.)
     5 | 1.498 to 1.501 mm (0.0590 to 0.0591 in.)

1. Completely remove the Plastigage.

15. INSPECT CRANKSHAFT THRUST CLEARANCE

1. Using a dial indicator, measure the thrust clearance while prying the crankshaft back and forth with a screwdriver.

   Standard thrust clearance:
     0.040 to 0.240 mm (0.0016 to 0.0094 in.)

   Maximum thrust clearance:
     0.30 mm (0.0118 in.)
   If the thrust clearance is greater than the maximum, replace the thrust washers as a set.

   Thrust washer thickness:

     STD | 2.430 to 2.480 mm (0.0957 to 0.0976 in.)
     O/S 0.125 | 2.493 to 2.543 mm (0.0981 to 0.1001 in.)
     O/S 0.250 | 2.680 to 2.730 mm (0.1055 to 0.1074 in.)

16. INSPECT CRANKSHAFT OIL CLEARANCE

1. Clean each main journal and bearing.

1. Check each crankshaft journal and bearing for pitting and scratches.
   If the journal or bearing is damaged, replace the bearings. If necessary, grind or replace the crankshaft.

1. Place the crankshaft on the cylinder block.

1. Lay a strip of Plastigage across each journal.

1. Install the 5 crankshaft bearing caps with the 10 bolts.

   NOTICE:
     Do not turn the crankshaft.

1. Remove the 10 bolts and 5 crankshaft bearing caps.

1. Measure the Plastigage at its widest point.

   Standard oil clearance:

     STD | 0.030 to 0.048 mm (0.0012 to 0.0019 in.)
     O/S 0.25, O/S 0.50 | 0.037 to 0.077 mm (0.0015 to 0.0030 in.)

   Maximum clearance:
     0.10 mm (0.0039 in.)
   If the oil clearance is greater than the maximum, replace the bearings. If necessary, grind or replace the crankshaft.

   HINT:
     If replacing the cylinder block sub-assembly, the bearing standard clearance will be within standard value.

   Standard:
     0.030 to 0.048 mm (0.0012 to 0.0019 in.)

   HINT:
     If using a standard bearing, replace it with one having the same number. If the number of the bearing cannot be determined, select the correct bearing by adding together the numbers imprinted on the cylinder block and crankshaft, then selecting the bearing with the same number as the total. There are 5 sizes of standard bearings, marked 2, 3, 4, 5 and 6.

   Bearing size:

     Item | Number Mark
     Cylinder block | 1 | 2 | 3
     Crankshaft | 1 | 2 | 3 | 1 | 2 | 3 | 1 | 2 | 3
     Use bearing | 2 | 3 | 4 | 3 | 4 | 5 | 4 | 5 | 6

   HINT:
     EXAMPLE: Cylinder block "2" + crankshaft "1"
     = Total number 3 (Use bearing "3")

   Reference:
     Cylinder block main journal bore diameter:

     Mark | Diameter
     1 | 75.000 to 75.006 mm (2.9528 to 2.9530 in.)
     2 | 75.006 to 75.012 mm (2.9530 to 2.9532 in.)
     3 | 75.012 to 75. 018 mm (2.9532 to 2.9535 in.)

     Crankshaft journal diameter:

     Mark | Diameter
     1 | 69.994 to 70.000 mm (2.7557 to 2.7559 in.)
     2 | 69.988 to 69.994 mm (2.7554 to 2.7557 in.)
     3 | 69.982 to 69.988 mm (2.7552 to 2.7554 in.)

     Standard sized bearing center wall thickness:

     Mark | Diameter
     2 | 2.482 to 2.485 mm (0.0977 to 0.0978 in.)
     3 | 2.485 to 2.488 mm (0.0978 to 0.0980 in.)
     4 | 2.488 to 2.491 mm (0.0980 to 0.0981 in.)
     5 | 2.491 to 2.494 mm (0.0981 to 0.0982 in.)
     6 | 2.494 to 2.497 mm (0.0982 to 0.0983 in.)

1. Completely remove the Plastigage.

17. INSPECT OIL CHECK VALVE SUB-ASSEMBLY

1. Push the valve with a wooden stick to check if it is stuck.
   If stuck, replace the check valve.

18. INSPECT NO. 1 OIL NOZZLE SUB-ASSEMBLY

1. Check the oil nozzles for damage or clogging.
   If necessary, replace the oil nozzle.

19. CLEAN CYLINDER BLOCK SUB-ASSEMBLY

1. Using a gasket scraper, remove all the gasket material from the top surface of the cylinder block.

1. Using a soft brush and solvent, thoroughly clean the cylinder block.

20. INSPECT CYLINDER BLOCK SUB-ASSEMBLY

1. Inspect for flatness.

   1. Using a precision straightedge and feeler gauge, measure the surface contacting the cylinder head cap for warpage.

      Maximum warpage:
        0.10 mm (0.0039 in.)
      If warpage is greater than the maximum, replace the cylinder block.

1. Visually check the cylinder for vertical scratches.
   If deep scratches are present, rebore all the 4 cylinders. If necessary, replace the cylinder block.

1. Inspect the cylinder bore diameter.

   HINT:
     There are 3 sizes of the standard cylinder bore diameter, marked 1, 2 and 3 accordingly. The mark is stamped on the lower left rear of the cylinder block.

   1. Using a cylinder gauge, measure the cylinder bore diameter at positions A, B and C in the thrust and axial directions.

      Standard diameter:

        Mark 1 | Mark 2 | Mark 3
        96.000 to 96.010 mm (3.7795 to 3.7799 in.) | 96.010 to 96.020 mm (3.7799 to 3.7803 in.) | 96.020 to 96.030 mm (3.7803 to 3.7807 in.)

      Maximum diameter:

        STD | O/S 0.50 | O/S 0.75 | O/S 1.00
        96.23 mm (3.7886 in.) | 96.73 mm (3.8082 in.) | 96.98 mm (3.8181 in.) | 97.23 mm (3.8279 in.)

      If the diameter is greater than the maximum, rebore all the 4 cylinders. If necessary, replace the cylinder block.

1. Remove the cylinder ridge.
   If the wear is less than 0.2 mm (0.008 in.), using a ridge reamer, grind the top of the cylinder.

21. CLEAN PISTON

1. Using a gasket scraper, remove the carbon from the piston top.

1. Using a groove cleaning tool or broken ring, clean the piston ring grooves.

1. Using solvent and a brush, thoroughly clean the piston.

   NOTICE:
     Do not use a wire brush.

22. INSPECT WITH PISTON SUB-ASSEMBLY

1. Inspect the piston oil clearance.

   HINT:
     There are 3 sizes of the standard piston diameter, marked "1", "2" and "3" accordingly. The mark is stamped on the piston top.

   1. Using a micrometer, measure the piston diameter at right angles to the piston center line, the indicated distance from the piston head.

      Distance:
        63.63 mm (2.5051 in.)

      Piston diameter:

        Piston | Mark | Diameter
        STD | Mark 1 | 95.92 to 95.93 mm (3.77637 to 3.77676 in.)
        STD | Mark 2 | 95.93 to 95.94 mm (3.77676 to 3.77715 in.)
        STD | Mark 3 | 95.94 to 95.95 mm (3.77716 to 3.77755 in.)
        O/S 0.50 | - | 96.42 to 96.70 mm (3.7960 to 3.8070 in.)
        O/S 0.75 | - | 96.67 to 96.95 mm (3.8058 to 3.8169 in.)
        O/S 1.00 | - | 96.92 to 97.20 mm (3.8157 to 3.8267 in.)

   2. Measure the cylinder bore diameter in the thrust directions.

   3. Subtract the piston diameter measurement from the cylinder bore diameter measurement.

      Standard oil clearance:
        0.070 to 0.090 mm (0.0028 to 0.0035 in.)

      Maximum oil clearance:
        0.14 mm (0.0055 in.)
      If the oil clearance is greater than the maximum, replace all the 4 pistons and rebore all the 4 cylinders.
      If necessary, replace the cylinder block.

      HINT:
        Use a piston with the same number mark as the cylinder diameter marked on the cylinder block.

1. Using a micrometer, measure the piston pin diameter.

   Piston pin diameter:
     33.996 to 34.008 mm (1.3384 to 1.3389 in.)

1. Inspect the piston pin fit.

   1. At 80°C (176°F), check that the piston pin can be pushed into the piston pin hole with your thumb.
      If the pin can be installed at a lower temperature, replace the piston and pin as a set.

23. INSPECT PISTON RING SET

1. Inspect the piston ring groove clearance.

   1. Using a feeler gauge, measure the clearance between a new piston ring and the wall of the ring groove.

      Standard groove clearance:

        No. 1 | No. 2 | Oil
        0.091 to 0.135 mm (0.0036 to 0.0053 in.) | 0.090 to 0.130 mm (0.0036 to 0.0051 in.) | 0.030 to 0.075 mm (0.0012 to 0.0027 in.)

      Maximum groove clearance:
        0.20 mm (0.079 in.)
      If the clearance is greater than the maximum, replace the piston.

1. Inspect the piston ring end gap.

   1. Insert the piston ring into the cylinder bore.

   2. Using a piston, push the piston ring a little beyond the bottom of the ring travel and 120 mm (4.72 in.) from the top of the cylinder block.

   3. Using a feeler gauge, measure the end gap.

      Standard end gap:

        No. 1 | No. 2 | Oil
        0.27 to 0.39 mm (0.0106 to 0.0154 in.) | 0.47 to 0.57 mm (0.0185 to 0.0224 in.) | 0.20 to 0.40 mm (0.0079 to 0.0157 in.)

      Maximum end gap:

        No. 1 | No. 2 | Oil
        0.85 mm (0.0335 in.) | 1.07 mm (0.0421 in.) | 0.77 mm (0.0303 in.)

      If the end gap is greater than the maximum, replace the piston ring.
      If the end gap is greater than the maximum, even with a new piston ring, rebore all the 4 cylinders or replace the cylinder block.

24. INSPECT CONNECTING ROD SUB-ASSEMBLY

1. Using a rod aligner and feeler gauge, check the connecting rod alignment.

   1. Check if it is bend.

      Maximum bend:
        0.03 mm (0.0012 in.) per 100 mm (3.94 in.)
      If bend is greater than the maximum, replace the connecting rod sub-assembly.

   2. Check if the rod is twisted.

      Maximum twist:
        0.15 mm (0.0059 in.) per 100 mm (3.94 in.)
      If twist is greater than the maximum, replace the connecting rod sub-assembly.

25. INSPECT PISTON PIN OIL CLEARANCE

1. Inspect the piston pin oil clearance.

   1. Using a caliper gauge, measure the inside diameter of the connecting rod bush.

      Bush inside diameter:

        Size Mark | Diameter
        A | 34.012 to 34.016 mm (1.3390 to 1.3392 in.)
        B | 34.016 to 34.020 mm (1.3392 to 1.3393 in.)
        C | 34.020 to 34.024 mm (1.3392 to 1.3395 in.)

   2. Subtract the piston pin diameter measurement from the bush inside diameter measurement.

      Standard oil clearance:
        0.012 to 0.024 mm (0.0005 to 0.0009 in.)

      Maximum oil clearance:
        0.03 mm (0.012 in.)
      If the oil clearance is greater than the maximum, replace the bush.
      If necessary, replace the piston and piston pin with a new piston and pin set.

26. INSPECT CONNECTING ROD BOLT

1. Using a vernier caliper, measure the tension portion of the connecting rod bolt.

   Standard diameter:
     8.500 to 8.600 mm (0.3346 to 0.3385 in.)

   Minimum diameter:
     8.30 mm (0.3268 in.)
   If the diameter is less than the minimum, replace the bolt.

27. INSPECT NO. 1 BALANCE SHAFT SUB-ASSEMBLY

1. Using a cylinder gauge, measure the inside diameter of the balance shaft bearing.

   Bearing inside diameter:

     No. 1 | No. 2 | No. 3
     42.000 to 42.020 mm (1.6535 to 1.6543 in.) | 41.000 to 41.020 mm (1.6142 to 1.6150 in.) | 32.000 to 32.020 mm (1.2598 to 1.2606 in.)

1. Using a micrometer, measure the outside diameter of the balance shaft main journals.

   Main journal diameter:

     No. 1 | No. 2 | No. 3
     41.941 to 41.960 mm (1.6512 to 1.6520 in.) | 40.931 to 40.950 mm (1.6115 to 1.6122 in.) | 31.941 to 31.960 mm (1.2575 to 12583 in.)

1. Subtract the outside diameter of the balance shaft main journal from the inside diameter to the balance shaft bearing.

   Standard clearance:

     No. 1 | No. 2 | No. 3
     0.040 to 0.079 mm (0.0016 to 0.0031 in.) | 0.040 to 0.079 mm (0.0016 to 0.0031 in.) | 0.050 to 0.089 mm (0.0020 to 0.0035 in.)

   Maximum oil clearance:

     No. 1 | No. 2 | No. 3
     0.18 mm (0.0071 in.) | 0.19 mm (0.0075 in.) | 0.18 mm (0.0071 in.)

   If the clearance is greater than the maximum, replace the cylinder block and balance shaft.

28. INSPECT NO. 2 BALANCE SHAFT SUB-ASSEMBLY

1. Using a cylinder gauge, measure the inside diameter of the balance shaft bearing.

   Bearing inside diameter:

     No. 1 | No. 2 | No. 3
     42.000 to 42.020 mm (1.6535 to 1.6543 in.) | 41.000 to 41.020 mm (1.6142 to 1.6150 in.) | 32.000 to 32.020 mm (1.2598 to 1.2606 in.)

1. Using a micrometer, measure the outside diameter of the balance shaft main journals.

   Main journal diameter:

     No. 1 | No. 2 | No. 3
     41.941 to 41.960 mm (1.6512 to 1.6520 in.) | 40.931 to 40.950 mm (1.6115 to 1.6122 in.) | 31.941 to 31.960 mm (1.2575 to 12583 in.)

1. Subtract the outside diameter of the balance shaft main journal from the inside diameter to the balance shaft bearing.

   Standard clearance:

     No. 1 | No. 2 | No. 3
     0.040 to 0.079 mm (0.0016 to 0.0031 in.) | 0.040 to 0.079 mm (0.0016 to 0.0031 in.) | 0.050 to 0.089 mm (0.0020 to 0.0035 in.)

   Maximum oil clearance:

     No. 1 | No. 2 | No. 3
     0.18 mm (0.0071 in.) | 0.19 mm (0.0075 in.) | 0.18 mm (0.0071 in.)

   If the clearance is greater than the maximum, replace the cylinder block and balance shaft.

29. INSPECT CRANKSHAFT

1. Inspect for circle runout.

   1. Place the crankshaft on V-blocks.

   2. Using a dial indicator, measure the circle runout at the center journal.

      Maximum circle runout:
        0.03 mm (0.0012 in.)
      If the circle runout is greater than the maximum, replace the crankshaft.

1. Inspect the main journals and crank pins.

   1. Using a micrometer, measure the diameter of each main journal and crank pin.

      Main journal diameter:

        Mark 1 | Mark 2 | Mark 3
        69.994 to 70.000 mm (2.75566 to 2.75590 in.) | 69.988 to 69.994 mm (2.75543 to 2.75566 in.) | 69.982 to 69.988 mm (2.75519 to 2.75543 in.)

      Crank pin diameter:

        Mark 1 | Mark 2 | Mark 3
        58.994 to 59.000 mm (2.32259to 2.32283 in.) | 58.988 to 59.994 mm (2.32236 to 2.32259 in.) | 58.982 to 58.988 mm (2.32212 to 2.32239 in.)

      If the diameter is not as specified, check the oil clearance. If necessary, grid or replace the crankshaft.

   2. Check each main journal and crank pin for taper and out-of-round as shown.

      Maximum taper and out-of-round:
        0.020 mm (0.0008 in.)
      If the taper and out-of-round is greater than the maximum, replace the crankshaft.

1. If necessary, grind and hone the main journals and/or crank pins.

   1. Grind and hone the main journals and/or crank pins to the finished undersized diameter.

   2. Install new main journal and/or crankshaft pin undersized bearing.

30. INSPECT CRANKSHAFT BEARING CAP BOLT

1. Using a vernier caliper, measure the minimum diameter of the compressed thread at the measuring point.

   Standard diameter:
     13.500 to 14.000 mm (0.5315 to 0.5512 in.)

   Minimum diameter:
     12.60 mm (0.4961 in.)
   If the diameter is less than the minimum, replace the bolt.