Piston Clearance; Ring Groove Clearance; Piston Pin - Suzuki Wagon R Plus RB310 Service Manual

6A2-72 ENGINE MECHANICAL (M13 ENGINE)

Piston clearance

Measure cylinder bore diameter and piston diameter to find their
difference which is piston clearance. Piston clearance should be
within specification as given below. If it is out of specification,
rebore cylinder and use oversize piston.
Piston clearance
Standard: 0.032 – 0.061 mm (0.0013 – 0.0024 in.)
NOTE:
Cylinder bore diameters used here are measured in
thrust direction at two positions.
"a": 19.5 mm (0.77 in.)

Ring groove clearance

Before checking, piston grooves must be clean, dry and free of
carbon deposits.
Fit new piston ring (1) into piston groove, and measure clearance
between ring and ring land by using thickness gauge (2). If clear-
ance is out of limit, replace piston.
Ring groove clearance
Top ring
Standard: 0.03 – 0.07 mm (0.0012 – 0.0028 in.)
Limit: 0.12 mm (0.0047 in.)
2nd ring
Standard: 0.02 – 0.06 mm (0.0008 – 0.0024 in.)
Limit: 0.10 mm (0.0039 in.)
Oil ring
Standard: 0.03 – 0.17 mm (0.0012 – 0.0067 in.)

Piston pin

Visual inspection
Check piston pin, connecting rod small end bore and piston bore
for wear or damage, paying particular attention to condition of
small end bore bush. If pin, connecting rod small end bore or pis-
ton bore is badly worn or damaged, replace pin, connecting rod
and/or piston.