Generac Power Systems CorePower 6/7 kW 60 Hz Diagnostic Repair Manual page 74

Section 4.4
Troubleshooting Flowcharts
Problem 23 – Engine Starts Hard and Runs Rough / Lacks Power / Backfires
Problem 23 – Engine Starts Hard and Runs Rough / Lacks Power / Backfires
TEST 60 – CHECK
FUEL SUPPLY AND GOOD
PRESSURE
BAD
FIND AND CORRECT
CAUSE OF NO FUEL
OR LOW PRESSURE
BAD
TEST 67 – CHECK
IGNITION MAGNETOS
BAD
ADJUST OR
REPLACE
Page 72
IF RECONFIGURED TO LP GAS,
VERIFY THAT PROPER
PROCEDURE WAS FOLLOWED.
(REFER TO SECTION 1.3)
REPLACE CHOKE SOLENOID
TEST 64 –
GOOD
CHECK FOR
IGNITION SPARK
READJUST
CHECK
FLYWHEEL
KEY
GOOD
TEST 63 – CHECK
CHOKE SOLENOID
BAD
TEST 65 –
CHECK SPARK
PLUGS
BAD
CLEAN, REGAP
OR REPLACE
TEST 13 – CHECK
AND ADJUST
BAD
ENGINE
GOVERNOR
GOOD
TEST 66 – CHECK
ENGINE
GOOD
COMPRESSION
BAD
REFER TO ENGINE
SERVICE MANUAL
PART 4
ENGINE/DC CONTROL
CHECK AIR FILTER -
REPLACE AS NEEDED
READJUST
BAD
TEST 70 –
CHECK AND
GOOD
ADJUST VALVES
GOOD