Inspect Piston Diameter And Oil Clearance; Inspect Clearance Between Wall Of Ring Groove And New Piston Ring; Inspect Piston Ring End Gap - Toyota 7M-GE Repair Manual

EM-76
ENGINE MECHANICAL - Cylinder Block
(c) Using a soft brush and solvent, thoroughly clean the
piston. -_
CAUTION:
Do not damage the piston.
linder
rface
3.
INSPECT PISTON DIAMETER AND OIL CLEARANCE
(a) Using a micrometer, measure the piston diameter at a
right angle to the piston pin hole center line, 22 mm
(0.87 in.) from the piston head.
Standard diameter:
,
7M-GE STD size 62.00 - 62.96
mm
(3.2636
- 3.2666 in.)
O/S O.SO 63.40 - 63.4s mm
(3.263S - 3.2664 in.)
7M-GTE STD size 62.91 - 62.96 mm
(3.2642 - 3.2661 in.)
O/S 0.50 83.41 - 63.46 mm
(3.2639 - 3.2658 in.)
(b) Measure the cylinder bore diameter in thrust direc-
tions.
(See step 5 on page EM-731
(c) Subtract the piston diameter measurement from the
cylinder bore diameter measurement.
Standard oil clearance:
7M-GE 0.08 - 0.10 mm (0.0031 - 0.0039 in.)
7M-GTE 0.07 - 0.09 mm (0.0026 - 0.0035 in.)
Maximum oil clearance: 0.13 mm (0.0051 in.)
If the oil clearance is greater than maximum, replace the
piston. rebore all six cylinders and replace all
six pistons. If necessary, replace the cylinder block.
INSPECT CLEARANCE BETWEEN WALL OF RING
GROOVE AND NEW PISTON RING
Using a thickness gauge, measure the clearance between
new piston ring and the wall of the piston ring groove.
Ring groove clearance: No. 1
0.03 - 0.07 mm
(0.0012 - 0.0026 in.)
No. 2 0.02 - 0.06 mm
(0.0006 - 0.0024 in.)
If the clearance is not within specification, replace the
piston.
4. INSPECT PISTON RING END GAP
(a) Insert the piston ring into the cylinder bore.
(b)
Using a piston, push the piston ring a little beyond
the bottom of the ring travel.
(I 10 mm (4.33 in.) from top surface of cylinder
block)