Briggs & Stratton 272147 Repair Manual page 44

TM
Vanguard Twin-Cylinder OHV Liquid-Cooled Engine
Section 4 - Engine Overhaul
necessary to check pistons and rings since a new
oversized piston assembly will be used.
Disassemble Piston and Connecting Rod
1. Remove piston top and center rings using ring
expander, Tool
#19340
a. Remove top oil scraper ring, then bottom
scraper ring.
b. Remove expander.
TOOL #19340
PISTON
Fig. 73
2. Disassemble piston from connecting rod, Fig. 74.
a. Remove piston pin locks.
b. Piston pin is a slip fit in piston and connecting
rod.
Keep pistons and connecting rods together as an
assembly. Do not mix.
Fig. 74
, Fig. 73.
Check Piston And Rings
If the cylinder is not going to be resized and the piston
shows no signs of scoring, the piston should be checked.
1. Check side clearance of ring grooves using NEW
rings, Fig. 75.
Compression Rings:
a. If a
.005" (0.12 mm)
inserted, the ring groove is worn. The piston
must be replaced.
Oil Rings:
b. If a
.007" (0.18 mm)
inserted, the ring groove is worn. The piston
must be replaced.
NEW PISTON RING
Fig. 75
2. Check ring end gap, Fig. 76.
a. Clean carbon from end of rings and insert
approximately 1" (25 mm) into cylinder.
Reject Dimension (all): .030" (0.76 mm)
feeler gauge can be
feeler gauge can be
Page 39