Chevrolet 10 Series 1970 Service Manual page 368

ENGINE FUEL 6M -4
to Section 6M of the O verhaul Manual under the carb u re­
to r being s erviced .
Rochester M
• Float
• Choke Rod
• Choke Unloader
Rochester 2 G
• Float
• A c c e le ra to r Pump
• Idle Vent
• Choke Rod
Rochester 2 G V
•
Float
• A c c e le ra to r Pump
• Idle Vent
• Choke Rod
• Choke Unloader
H o lle y M o d e l 4 1 5 0 G
• Float
• Idle Vent
• A c c e le ra to r Pump
• Choke Unloader
Carburetor Removal
Flooding, stumble on acceleration and other p e r fo r m ­
ance com plaints a re, in many instances, caused by the
presence o f dirt, w ater, o r other fo reign m atter in the
carburetor. To aid in diagnosing the cause o f the com ­
plaint, the carb u retor should be carefu lly rem oved from
the engine without draining the fuel from the bowl. The
contents of the fuel bowl m ay then be examined fo r con­
tamination as the ca rb u retor is disassem bled.
1. Rem ove a ir clean er and gasket.
2. Disconnect fuel and vacuum lines from carb u retor.
3. Disconnect choke cable o r rod.
4. Disconnect a c celera to r linkage.
5. If equipped with automatic transm ission, disconnect
T V linkage.
6. Rem ove carb u retor
carbu retor.
Carburetor Test Before Installation
It is good shop p ra ctice to f ill the carb u retor bowl b e ­
fo re installin g the ca rb u retor.
on the starting m otor and b attery and reduces the p o s s i­
b ility of backfirin g while attem pting to start the engine.
A fuel pump clamped to the bench, a sm all supply of fuel
and the n ecessary fittings
fille d and the operation of the float and intake needle and
seat to be checked. O perate the throttle le v e r se v e ra l
tim es and check the discharge from the pump jets b efore
in stallin g the carbu retor.
Carburetor Installation
1. Be certain throttle body and intake m anifold sealing
su rfaces are clean.
2. Install new carb u retor to m anifold flange gasket (if
requ ired ).
3. Install carbu retor o v e r m anifold studs.
4. Start vacuum and fuel lines at carburetor.
5. In stall attaching nuts and tighten secu rely.
6. Tighten fuel and vacuum lines.
7. Connect and adjust a c c e le ra to r and TV linkage.
8. Connect choke cable o r choke rod.
attaching nuts a n d rem ove
This reduces the strain
enable the carb u retor to be
S P R IN G
FILTER
F ig . 8 c —Fuel F ilte r (B ro nze-T ype)
9. Adjust id le speed and
clean er.
Fuel Filter Maintenance
1. Disconnect fuel line connection at inlet fuel filt e r nut.
2. Rem ove inlet fuel filt e r nut fro m ca rb u retor with a
box wrench o r socket.
3. Rem ove filte r elem ent and spring (fig . 8C and 9C).
4. Check bronze elem ent fo r restrictio n by blowing on
cone end, elem ent should allow a ir to pass fre e ly .
5. Check paper elem ent by blowing on fuel inlet end.
If filt e r does not allow a ir to pass fr e e ly , replace
FILTER
F ig . 9 c —Fuel F ilte r (P ap er-T ype)
m ixture, then in stall a ir
CHEVROLET TRUCK SERVICE MANUAL