How to Diagnose Generac Generator Problems

Engine Runs but no AC Output

• 1

  Verify that both circuit breakers are closed by checking the breaker switches at the control panel on the side of the generator. Reset the circuit breaker if necessary.

• 2

  Check the power cord or extension cord leading to the appliance. Verify that extension cord connections are secure. Substitute a different power cord or extension cord.

• 3

  Try another device or appliance on the same line to exclude an inoperative or defective appliance.

Engine Slows Excessively when Power Loads are Applied

• 4

  Determine if a short exists in any device or appliance connected to the generator.

• 5

  Disconnect multiple devices or appliances one at a time to identify which device is creating the excessive load.

• 6

  Make sure you aren't overloading the generator by connecting devices with wattage demands that exceed the generator's specifications. Consult the Wattage Reference Guide in the Owner's Manual to total the wattage of all devices connected to the generator.

Engine Won't Start or Runs Rough and Falters

• 7

  Check the air filter and replace if it appears dirty.

• 8

  Replace a worn or fouled spark plug. The spark plug should be replaced annually as part of routine maintenance. Verify that the spark plug wire is securely attached to the spark plug terminal.

• 9

  Make sure the fuel tank contains adequate fuel. If the generator was stored for a period of time with fuel in the tank, drain the fuel tank and refill with fresh fuel.

• 10

  Allow a cold engine to warm up fully before turning the choke knob on top of the engine to the "Off" position. Once the engine is hot, make sure the choke knob is not left "On."

• 11

  Check the oil level in the crankcase and add oil if necessary.

• 12

  Contact a Generac Authorized Service Facility if fuel mixture is incorrect, an intake valve is stuck or the engine has lost compression.

Engine Shuts Down During Operation

• 13

  Make sure the fuel tank contains adequate fuel. If the generator was stored for a period of time with fuel in the tank, drain the fuel tank and refill with fresh fuel.

• 14

  Check the oil level in the crankcase and add if necessary. The GP 3250 has a low oil shutdown system that automatically turns off the engine if the oil level in the crankcase is insufficient.

• 15

  Contact a Generac Authorized Service Facility if any other fault in the engine is suspected.

Engine Lacks Power

• 16

  Make sure you aren't overloading the generator by connecting devices with wattage demands that exceed the generator's specifications. Consult the Wattage Reference Guide in the Owner's Manual to total the wattage of all devices connected to the generator.

• 17

  Check the air filter and replace if it appears dirty.

• 18

  Contact a Generac Authorized Service Facility if any other fault in the engine is suspected.