Generac Power Systems 53187 - Manual (Page 70)

PART 2
ENGINE MECHANICAL
1
SECTION 2.4
DISASSEMBLY AND INSPECTION
Section 2.4
DISASSEMBLY AND INSPECTION
General
Before starting the disassem bly and Inspection pro­
cedure, check the folow ing:
GCarefully Inspect the cylinder block and cylinder
head for dam age and evidence of w ater leakage.
DUse pressure air to blow out all oil holes, m ake sure
none of the holes are plugged.
□w ash al parts to rem ove dirt, dust, dirty oil and
carbon deposits.
□clean all carbon deposits from the piston, cylinder
head and valves. Make sure these parts are not
dam aged. Pay special attention to alum inum alloy
parts.
□Place m atch m arks on m ating parts for correct
reassem bly.
Rocker Arm Assembly
Rem ove bolt at end of rocker arm shaft. Rem ove
ROCKER ARM, ROCKER ARM BRACKET and
springs. Pull out the spring pin from from the No. 1
cylinder ROCKER ARM BRACKET. Rem ove ROCKER
ARMS, SPRINGS and BRACKETS.
Rocker arm
\y'
Rocker arm bracket
Figure 1. Rocker Arm s and Rocker Arm Brackets
Use a m icrom eter to check the outside diam eter of
the rocker arm shaft If allow able lim its are exceeded,
replace the rocker arm shaft.
W ear of rocker arm shaft! o )
Standard dimension Allowable limit
11.65 to 11.67 mm 11.57 mm
■ i______ ^^__________ 1______ 1 ]_
1/ _ ^ “
I 1 I
t 1 t
Figure 2. W ear Lim its of Rocker Arm Shaft
Measure the inside diam eter of the rocker arm . Cal­
culate the clearance betw een the rocker arm and the
rocker arm shaft. If allow able lim its are exceeded,
replace the part(s).
Figure 3. Rocker Arm to Shaft Clearance
Check the valve stem face for step w ear or scoring.
Slight w ear or scoring m ay be corrected using an oil
stone or grinder (Figure 4).
Figure 4. Removing Slight Wear or Scoring
PAGE 2.4-1