Inspect Piston Ring Groove Clearance; Inspect Piston Ring End Gap - Toyota 3VZ–FE Troubleshooting Manual

EG–112
ENGINE TROUBLESHOOTING
B.
C.
(a) Insert the piston ring into the cylinder bore.
(b) Using a piston, push the piston ring a little beyond the bottom
(c) Using a thickness gauge, measure the ring end gap.
– ENGINE MECHANICAL

Inspect piston ring groove clearance

Using a thickness gauge, measure the clearance between
new piston ring and the wall of the piston ring groove.
Ring groove clearance:
No.1
0.010–0.080 mm (0.0004–0.0031 in.)
No.2
0.030–0.070 mm (0.0012–0.0028 in.)
If the clearance is greater than maximum, replace the piston.

Inspect piston ring end gap

of the ring travel, 100 mm (3.94 in.) from the top of the cylinder
block.
Standard ring end gap:
No.1
0.280–0.500 mm (0.0110–0.0197 in.)
No.2
0.380–0.600 mm (0.0150–0.0236 in.)
Oil (Side rail)
0.150–0.570 mm (0.0059–0.0224 in.)
Maximum ring end gap:
No.1
1.10 mm (0.0433 in.)
No.2
1.20 mm (0.0472 in.)
Oil (Side rail)
1.17 mm (0.0461 in.)
If the end gap is greater than maximum, replace the piston
ring. If the end gap is greater than maximum, even with a new
piston ring, rebore all the six cylinders or replace the cylinder
block.