Cylinder Block: Inspection

CLEAN CYLINDER BLOCK
1. Using a gasket scraper, remove all the gasket material from the top surface of the cylinder block.
2. Using a soft brush and solvent, thoroughly clean the cylinder block.
Fig 1: Removing All Gasket Material From Top Surface Of Cylinder Block
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT CYLINDER BLOCK
1. Inspect for flatness.
  Using a precision straight edge and a feeler gauge, measure the surfaces contacting the cylinder head and main bearing cap for a warp.
  1. Maximum warpage: 0.07 mm (0.0028 in.)
  If the warp is greater than the maximum, replace the cylinder block.
  
  Fig 2: Inspect Cylinder Block For Flatness
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Visually check the cylinder for vertical scratches.
  If deep scratches are found, rebore all the 8 cylinders and replace all the 8 pistons (See REPLACEMENT ). If necessary, replace the cylinder block.
  
  Fig 3: Visually Checking Cylinder
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. 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 top of the cylinder block.
  
  Fig 4: Inspecting Cylinder Bore Diameter
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Using a cylinder gauge, measure the cylinder bore diameter at positions A, B and C in the thrust and axial directions.
  
  Fig 5: Measuring Cylinder Bore Diameter Using Cylinder Gauge
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard diameter:
  
  Fig 6: Standard Diameter Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Maximum diameter: 94.23 mm (3.7098 in.)
  
  Fig 7: Maximum Diameter Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If the diameter is greater than the maximum, rebore all the 8 cylinders and replace all the 8 pistons (See REPLACEMENT ). If necessary, replace the cylinder block.
4. 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.
  
  Fig 8: Removing Cylinder Ridge
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Using vernier calipers, measure the thread outside diameter of the main bearing cap bolt.
  1. Standard diameter: 10.760 - 10.970 mm (0.4236 - 0.4319 in.)
  2. Minimum diameter: 10.40 mm (0.4094 in.)
  If the diameter is less than the minimum, replace the cap bolt.
Fig 9: Measuring Thread Outside Diameter Of Main Bearing Cap Bolt Using Vernier Caliper
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
CLEAN PISTON
1. Using a gasket scraper, remove the carbon from the piston top.
  
  Fig 10: Removing Carbon From Piston Top Using Gasket Scraper
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Using a groove cleaning tool or broken ring, clean the piston ring grooves.
  
  Fig 11: Cleaning Piston Ring Grooves Using Groove Cleaning Tool
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Using solvent and a brush, thoroughly clean the piston.
  NOTE: Do not use a wire brush.
Fig 12: Cleaning Piston Using Solvent & Brush
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT PISTON AND CONNECTING ROD
1. Inspect the piston oil clearance.
  
  Fig 13: Piston Diameter Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  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 pin center line, 30.75 mm (1.2106 in.) from the piston head.
    Piston diameter:
    
    Fig 14: Measuring Piston Diameter Using Micrometer
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Measure the cylinder bore diameter in the thrust directions. (See step 2 above)
  3. Subtract the piston diameter from the cylinder bore diameter.
    1. Standard oil clearance: 0.090 - 0.111 mm (0.0035 - 0.0044 in.)
    2. Maximum oil clearance: 0.13 mm (0.0051 in.)
    If the oil clearance is greater than the maximum, replace all the 8 pistons and rebore all the 8 cylinders. (See REPLACEMENT ) If necessary, replace the cylinder block.
  HINT
  
  Use new cylinder block:
  
  Fig 15: Identifying Cylinder Block
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  - Use a piston with the same number mark as the cylinder diameter marked on the cylinder block.
  - The shape of the piston varies for the LH and the RH banks. The LH piston is marked as "LH" and "2L", and the RH piston as "RH" and "2R".
2. Inspect the piston ring groove clearance.
  
  Fig 16: Measuring Clearance Between Piston Ring & Wall Of Ring Groove
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Using a feeler gauge, measure the clearance between new piston ring and the wall of the ring groove.
  
  Ring groove clearance:
  
  Fig 17: Ring Groove Clearance Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If the clearance is not as specified, replace the piston.
3. Inspect the piston ring end gap.
  1. Insert the piston ring into the cylinder bore.
  2. Using a piston, push the piston ring to a little beyond the bottom of the ring travel, 105 mm (4.13 in.) from the top of the cylinder block.
  3. Using a feeler gauge, measure the end gap.
  Standard end gap:
  
  Fig 19: Standard End Gap Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Maximum end gap:
  
  Fig 20: Maximum End Gap Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  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 8 cylinders (See REPLACEMENT ) or replace the cylinder block.
  
  Fig 21: Measuring End Gap Using Feeler Gauge
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Inspect the piston pin fit.
  At 60°C (140°F), you should be able to push the piston pin into the piston pin hole with your thumb.
  
  Fig 22: Inspecting Piston Pin Fit
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Using a rod aligner and the feeler gauge, check the connecting rod alignment.
  
  Fig 23: Checking Connecting Rod Alignment Using Rod Aligner & Feeler Gauge
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Check for bend.
    1. Maximum bend: 0.05 mm (0.0020 in.) per 100 mm (3.94 in.)
    If bend is greater than maximum, replace the connecting rod assembly.
  2. Check for twist
    
    Fig 24: Checking For Twist
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. 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 assembly.
6. Inspect the piston pin oil clearance.
  1. Using a caliper gauge, measure the inside diameter of the connecting rod bushing.
    1. Bushing inside diameter: 22.005 - 22.014 mm (0.8663 - 0.8667 in.)
    Fig 25: Measuring Inside Diameter Of Connecting Rod Bushing Using Caliper Gauge
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Using a micrometer, measure the piston pin diameter.
    
    Fig 26: Measuring Piston Pin Diameter Using Micrometer
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Piston pin diameter: 21.997 - 22.006 mm (0.8660 - 0.8664 in.)
  3. Subtract the piston pin diameter from the bushing inside diameter.
    1. Standard oil clearance: 0.005 - 0.011 mm (0.0002 - 0.0004 in.)
    2. Maximum oil clearance: 0.05 mm (0.0020 in.)
    If the oil clearance is greater than the maximum, replace the bushing. If necessary, replace the piston and the piston pin as a set.
7. Using vernier calipers, measure the tension portion of the connecting rod bolt.
  
  Fig 27: Measuring Tension Portion Of Connecting Rod Bolt Using Vernier Caliper
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Standard diameter: 7.200 - 7.300 mm (0.2835 - 0.2874 in.)
  2. Minimum diameter: 7.00 mm (0.2756 in.)
  If the diameter is less than the minimum, replace the bolt.
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.
    
    Fig 28: Measuring Circle Runout At Center Journal Using Dial Indicator
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Maximum circle runout: 0.08 mm (0.0031 in.)
  If the circle runout is greater than the maximum, replace the crankshaft.
2. Inspect the main journals and the crank pins.
  1. Using a micrometer, measure the diameter of each main journal and crank pin.
    
    Fig 29: Measuring Diameter Of Main Journal & Crank Pin Using Micrometer
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Main journal diameter: 66.988 - 67.000 mm (2.6373 - 2.6378 in.)
    2. Crank pin diameter: 51.982 - 52.000 mm (2.0465 - 2.0472 in.)
    If the diameter is not as specified, check the oil clearance (See DISASSEMBLY ). If necessary, replace the crankshaft.
  2. Check each main journal and crank pin for taper and out-of-round as shown in Fig 29 .
    1. Maximum taper and out-of-round: 0.02 mm (0.0008 in.)
    If the taper and out-of-round is greater than the maximum, place the crankshaft.