Leaking Carburetor; Inconsistent Idle Speed; Reduced Power Output - Ford LRG-423 Service Manual

03-23 Auxiliary Systems 03-23
CARBURETOR DIAGNOSIS (Continued)
If a lean mixture is the cause of poor acceleration, the
fault may be an improperly adjusted accelerator pump,
a damaged accelerator pump piston cap, an
accelerating pump check valve that is missing,
damaged, or not seating, a fuel float level set too low,
a clogged main metering jet, or a restricted main fuel
passage. Air leaks are also responsible for a lean
mixture causing poor acceleration. Leaks may occur at
the carburetor base to the intake manifold, or the
intake manifold to the cylinder head. Cracks in the
assemblies or worn gaskets cause these air leaks.
Clean, adjust, repair or replace as necessary.
Inconsistent Idle Speed
Inconsistent idle speed is mostly a throttle-related
problem. An incorrect throttle linkage adjustment, a
binding throttle linkage, a sticking throttle shaft, or a
loose throttle shaft in the throttle body or bore can
cause inconsistent idle speed. A sticking fuel inlet
needle can also cause this problem. Repair, replace
or adjust as necessary.
Reduced Power Output
Reduced power output
opened, an improperly
is caused by a
adjusted throttl
throttle not opening fully, a main jet not suited for this
application, or clogged main jets, main fuel passage,
or air bleeds. Clean, adjust, repair, or replace as
necessary.
choke not fully
e linkage, a
Leaking Carburetor
The causes of a carburetor leaking fuel are loose fuel
connections or a cracked carburetor body. Repair or
replace as needed.