272144 Vanguard Twin Cylinder OHV BRIGGS & STRATTON.pdf

1. Measure valve stem diameter approximately
1-1/2” (38 mm) from end of valve, Fig. 15.
Replace valve if stem diameter is less than 0.233”
(5.92 mm).
1.5” (38 MM)
NOTE: Lightly coat valve stems with Valve Guide
Lubricant #93963 before installing valves.
Be sure valve guide lubricant is not on valve
face, seat or end of valve stem.
3. Install springs and valve spring retainers over
valve stems.
Fig. 15
2. Valve faces can be resurfaced to 45. See
Fig. 16 for dimensions for valves.
3. Lap the valves and seats with Valve Lapper
#19258 and Valve Lapping Compound #94150.
NOTE: In most instances it is more economical to
replace the valves than to reface them.
3/64” – 1/16”
(1.2 MM TO 1.6 MM)
1/32” (0.8 MM)
MINIMUM
Fig. 18
NOTE: Place a shop rag or short section of rubber
fuel line under valves inside combustion
chamber to hold valve in place while
compressing spring.
CAUTION
SEATING AREA CENTERED
ON VALVE FACE
PREVENT EYE INJURY!
• Wear eye protection when using Valve Spring
Compressor.
Fig. 16
ASSEMBLY
1. Use Valve Guide Driver (1) #19416 to install new
valve stem seals (2), Fig. 17.
a. Oil inner surface and lip of valve stem seal.
b. Press seal on to valve guide bushing until it
bottoms.
4. Temporarily install rocker studs (3) in cylinder
head.
5. Compress valve spring and retainer with Valve
Spring Compressor #19347 (5). Install the valve
retainer locks (4), Fig. 19.
Fig. 17
2. Install valves, Fig. 18.
Fig. 19
6. Make sure the retainer locks are seated into the
valve stem groove and valve retainer. Gradually
release pressure on the valve spring compressor.
Repeat procedure for other valve. Remove rocker
studs.
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