Piston Rings; Autolube Pump - Yamaha YT175J 1982 Service Manual

Piston rings
1. Check rings for scoring. If any severe
scratches are noticed, replace ring set.
2. Insert each ring into cylinder. Push
down approximately 20 mm (0.79 in) us-
ing piston crown to maintain right-angle
to bore. Measure installed end gap. If
beyond to tolerance, replace set.
Top/Second
Ring end gap (installed)
I
0.30 - 0.50
mm
(0.012 - 0.020 in)
3. With rings installed in grooves, insert
feeler gauge between ring and groove. If
beyond tolerance, replace ring and/or
piston as required.
Ring groove clearance
Top
0.04 - 0.08 mm (0.0016 - 0.0031 in)
Second 0.04 - 0.08
mm
(0.0016 - 0.0031 in)
3-9
Autolube pump
1. Troubleshooting and repair
a. Wear or an internal malfunction may
cause pump output to vary from the fac-
tory setting. This situation is, however,
extremely rare. If output is suspected,
check the following:
1) Obstructions in delivery line to pump
or from pump to cylinder.
2) Worn or damaged pump body seal
or crankcase cover seal.
3) Missing or improperly installed
check ball or spring.
4) Improperly installed or routed oil
delivery line(s).
5) Loose fitting(s) allowing air to enter
pump and/or engine.
b. If all inspections show no obvious pro-
blems and output is still suspect, con-
nect a delivery line from the pump to a
graduated container (cm
3 ).
Keep the
delivery line short.
If output is not to specification, replace
pump assembly.
Autolube Pump Specifications:
Pump color code: Green
Minimum stroke Maximum stroke
Pump stroke
length
0.20 - 0.25 mm 1.85 - 2.05 mm
. (0.08 - 0.01 in)
(0.07 - 0.08 in)
Minimum output Maximum output
Pump output at
0.814em
3
3.29 em
3
200 strokes
(0.029 Imp oz. (0.12 Imp oz.
0.028 USoz) 0.11 USoz)