Chevrolet 10 1971 Series Chassis Service Manual page 326

FUEL TANK AN D EXHAUST SYSTEMS 8-2
D R A IN IN G FUEL TANK
If the fuel tank does not incorporate a drain plug, it
will be necessary to siphon fuel from the tank when drain­
ing is needed. The following procedure is recommended.
1. Obtain approximately 10 feet of 3/8" I.D. hose and
cut a flap-type slit 18" from one end. Make this cut
in the direction of the shorter end of hose (See Fig­
ure 1).
2. Insert a small pipe nipple (slightly larger O.D. than
the hose I.D.) into the opposite end of hose.
3. Insert the nipple end of siphon hose into the fuel tank
filler neck with the natural curl of the hose pointed
down. Insert until the hose is heard to strike the
bottom of the tank.
4. With the opposite end of the hose in a suitable con­
tainer, insert an air hose in the downward direction
in the flap-type slit and trigger the flow of fuel.
Before draining be sure that the
CAUTION:
fuel tank gauge unit wire or battery negative
cable is disconnected.
Always drain gasoline from complete fuel sys­
tem including carburetor, fuel pump, all fuel
lines and fuel tank if the vehicle is to be stored
for any appreciable length of time. This pre­
caution will prevent accumulation of gum forma­
tion and resultant poor engine performance.
COMPONENT PART REPLACEMENT
(Refer to Illustrations)
G AUGE UNIT OR STRAINER
Replacement
The following procedure is intended as a general guide
only and will vary according to truck series and model.
1. Drain tank to a level below gauge unit mounting loca­
tion or if unit is inaccessible remove fuel tank.
10-30 CHEVROLET TRUCK SERVICE MANUAL