AJP PR4, Руководство по обслуживанию

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Chapter 5 – Fuel feed system
Service manual AJP PR3/PR4 5 - 2
TROUBLESHOOTING
The motor rotates but does not start:
 No fuel in the tank;
 The fuel does not reach the carburetor:

Fuel filter obstructed;

Fuel line obstructed;

Breathe hose fuel tank cap obstructed
or damaged;

Suction pipe obstructed;

Vacuum pipe damaged;

Fuel pump damaged.

Fuel excess (soaked engine):

Air filter obstructed;

Soaked carburetor.
 Intake air leak;
 Fuel contaminated:

Jets obstructed.
 Malfunctioning air lever (CHOKE) or air
sealing butterfly;
 Malfunctioning of the throttle;
 No spark in the spark plug (faulty ignition
system).
Lean mixture
 Clogged fuel jet;
 Faulty float valve;
 Very low float level;
 Restricted fuel line;
 Carburetor breather hose clogged;
 Fuel tank breather hose restricted;
 Intake air leak;
 Faulty throttle valve.
Rich mixture
 Closed air valve / CHOKE (malfunction of
the air lever / CHOKE);
 Air jet clogged;
 Faulty float valve;
 Very high float level;
 Very dirty air filter;
 Needle or needle diffuser with too much
wear;
 Main jet loosened.
The engine turns off, the start is
difficult or idling is irregular:
 Restricted fuel line;
 Fuel mixture very poor / rich;

Fuel contaminated / damaged:

Minimum jet clogged;
 Intake air leak;
 Idling out of adjustment;
 Breather in fuel tank cap clogged or
damaged;
 Dirty air filter;
 Mixture screw out of adjustment;
 Defective ignition system.
Backfire or failures during
acceleration:
 Poor mixture;
 Defective ignition system.
Underperforming (handling) and high
fuel consumption:
 Fuel system clogged;
 Defective ignition system.