Shibaura ST330, Workshop Manual

Page: 205 / 250

194
11) FUEL LEVEL SENDING UNIT
Description and Lo catio n
The fuel level send ing unit, 1, is mo unted on
top of the fuel tank, 2, and ex tends into th e
tank . Th e sending unit utilizes a float th e
raise and lo wers with the fuel level insid e
the tank . The float regulates a v ariable
resistan ce to g round, w hich translates into
movement of the fuel gaug e on th e
instru men t p anel. As th e float low ers (fuel
being co nsumed) inside the tank , th e ground
resistan ce in creases, ind icating less fuel on
the fuel gauge.
Removal
1. D isconnect th e negativ e ( － ) battery
cable fro m t he battery.
2 . D isconnect the two wiring harness leads,
3, attached to the termin als on the fuel
level sending un it, 1. Be sure to mak e
note of what terminal each lead is
conn ected to for ease of i nstallation.
3 . R emove th e five (5) retainin g screws
th at secure the sending unit, 1, to th e
fuel tank, 2.
4 . Carefully remove th e sending u nit, 1,
from the fuel tank, 2.
5 . R emove and discard the sealing g asket
from the sen ding un it.
Fuel Level Sending Unit Testing
1 . U s ing an ohmmeter, touch one test prob e
to terminal "A" of the send in g u nit,
touch th e o ther test p robe to ter minal
"B" of the sending unit. Observe the
reading on the ohmmeter.
2 . With th e send ing un it float in the down
position (tank emp ty ), th e ohmmeter
should indicate betw een 103 and 117
ohms. If the ohmmeter reading is not
within these sp ecifications, the sending
unit is defective and needs replaced.
3 . With the sender in th e up position (tank
full), the ohmmeter should indicate
between 0.8 and 5 oh ms. If the
ohmmeter reading is no t with in thes e
specification s, the sending unit is
defective and need s replaced.
Insta llatio n
Assembly o f the fu el level sending un it
generally fo llows th e disassemb ly in rev erse.
NOTE:
When a ttaching th e wiring ha rness leads to
the fu el level send ing unit, b e sure th e
Yello w/white wire is connected to th e
insulated terminal (center) on the sending
unit.
538Y
539Y
540Y
541Y