Generac Power Systems GP Series Diagnostic Repair Manual page 41

Diagnostic Flow Charts
Use the Flow Charts in conjunction with the numbered tests in this section. Test numbers used in the flow charts
correspond to the numbered tests. The first step in using the flow charts is to identify the correct problem on the
following pages. For best results, perform all tests in the exact sequence shown in the flow charts.
Problem 6 – Engine Starts Hard and Runs Rough
DOESN'T START,
STARTS HARD OR
RUNS ROUGH
Problem 7 – Battery Will Not Charge
Diagnostic Repair Manual
FUEL
TEST 22 – TESTING FUEL
SYSTEM
AIR FILTER RESTRICTED
TEST 15 – TEST IGNITION
IGNITION
SYSTEM
COMPRESSION
SYSTEM
ENGINE ISSUE / FAILURE
TEST 11 – CHECK
FUSE(S)
TEST 21 – TEST
ENGINE BATTERY
CHARGING CIRCUIT
TEST 12 – CHECK
BATTERY AND
CABLES
Section 5 Engine Diagnostic Tests
CHECK FUEL SUPPLY
PUMP
CHECK AND CORRECT
OIL LEVEL LOW,
REPLENISH OIL
SPARK
TEST 13 – TESTING
ENGINE SWITCH
TEST 19 – CHECK OIL
PRESSURE SWITCH
TEST 17 – INTERNAL
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