Yamaha LB50IIAC - Yamaha Engine and Transmission Oil Checks

3. Minimum plunger stroke adjustment
Set the dial gauge as shown in the
figure, and check to see if the plunger
stroke is correct while keeping the
engine idling.
a. To adjust the plunger stroke, first loosen
the locknut
b. Turn the adjusting bolt in or out for
proper adjustment
Turning the adjusting bolt clockwise
decreases the plunger stroke; while tur-
ning counterclockwise increases the
plunger stroke.
c. When the correct stroke is attained,
tighten the locknut.
Specified stroke:
LB50 II AC
l
LB80 II AC
Minimum stroke
0.20
N 0.25 mm
Maximum stroke
0.55
N 0.65 mm
I
0.80 N 0.95 mm
Pulley color code
Gray
l
Brown
Pulley adjust mark
_____/I__
I
_____/I__
Engine and transmission oil
1. Engine
a. Autolube oil
1. Adjust pulley
5 Locknut
2. Plunger
6. Adjusting plate
3 Min. stroke
7 Dial gauge stand {for oil pump)
4 Adjusting bolt
We recommend that first choice be Yamaha 2-cycle oil. If for any reason you should use ano-
ther type, the oil should meet or exceed BIA certification "TC-W". Check container top or la-
bel
for service specification. If above oils are not available, use a 30 or 40 wt 2-stroke oil for
air-cooled engines.
IIIIIWfiml
Under extremely cold conditions (O'C or below) 30 and 40 wt oils become very thick and will
not flow as readily to the Autolube pump. This may cause oil pump starvation. Yamaha 2-
cycle oil will flow normally to the pump at temperatures below 18'C,
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