Generac Power Systems 2500 Diagnostic Repair Manual page 3

Safety ........................................................................ ii
Read This Manual Thoroughly .................................. ii
Replacement Parts ................................................... ii
Section 1Pump Troubleshooting
Troubleshooting Flow Charts ....................................3
Diagnostic Tests .......................................................5
Test 1 – Verify Supply Water Source ........................5
Test 2 – Check Pump For Water Flow ......................5
Test 3 – Test High Pressure Hose ............................5
Test 4 – Check Spray Gun Assembly .......................5
Test 5 – Checking the Spray Nozzle .........................5
Test 6 – Checking for Air Leaks at the
Pump Water Inlet ......................................................6
Test 7 – Check or Replace Valves On
Axial and Triplex Pumps. ..........................................6
Section 2Engine Troubleshooting
Troubleshooting Flow Charts ..................................11
Diagnostic Tests .....................................................14
Test 14 – Check Battery and Cables ......................14
Test 15 – Check Voltage at Starter Contactor (SC) 14
Test 16 – Check START-RUN-STOP Switch .........14
Test 18 – Check Starter Motor ................................15
Test 24 – Test On/Off Switch ..................................15
Test 25 – Test OneWash Alert Panel .....................16
Test 26 – Check Ignition Spark ...............................17
Diagnostic Repair Manual
Test 27 – Check Spark Plugs .................................17
Test 29 – Check Carburetion ..................................18
Test 30 – Choke Test .............................................18
Test 33 – Check Valve Adjustment .........................19
Test 36 – Check Engine / Cylinder Leak
Down Test / Compression Test ..............................19
Test 38 – Check Flywheel ......................................20
Magneto Replacement/Adjustment .........................20
TEST 39 – Remove Shutdown Lead ......................21
Test 40 – Check / Adjust Governor .........................22
Test 45 – Check Oil Level Switch - all models ........22
Test 49 – Test Recoil Function ...............................23
Test 49A – Replace a Recoil Starter Rope .............23
Test 50 – Test Engine Function ..............................23
Test 51 – Verify Engine Running at
Rated Speed at No Load ........................................23
Test 52 – Verify Water Pressure Switch
is Functioning ..........................................................24
Section 3Disassembly
Residential Pump – Removal From Engine ............25
Commercial Pump – Removal From Engine ..........25
Pump Re-Assembly ................................................25
Section 4Electrical Data
Introduction .............................................................27
Electrical Formulas .................................................29
Table of Contents
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