Read the manual thoroughly and understand all of the instructions, cautions, and warnings before using this equipment. If any section of the manual is not understood, contact your nearest authorized dealer, or contact Generac Customer Service at 1-888-436-3722 (1-888-GENERAC), or www.generac.com with any questions or concerns. 

Draining fuel from a portable generator

To prevent the fuel from expiring and causing starting issues in the future, it is recommended to drain all fuel from the tank of a portable generator or pump before storing it for more than 30 days.

Note: Generac support recommends that generators are run dry before storage. This ensures leftover fuel does not contaminate the carburetor.

Environment

This article applies to Generac portable generators that are being prepared for long term storage (more than 30 days).

Methods to drain fuel

The method to drain fuel will vary depending on if your generator has a fuel shutoff switch (also known as the fuel valve, or petcock).

Before you begin

To properly drain fuel from your portable generator, you will need a fuel siphon and an approved container to drain the gas into.

How do I know if my generator has a fuel shutoff switch?

If your generator's model name does not include EFI (electronic fuel injection) it most likely has a fuel shutoff switch. Jump to Portable generators with a shutoff switch

The fuel shutoff switch is a metal valve, typically located directly below the gas tank near the carburetor. See below for an example of a fuel shutoff switch on the GP9200E:

If your generator has EFI in the model number (such as the XT8500EFI) it does not have a fuel shutoff switch. Jump to Portable generators without a shutoff switch

Portable generators with a fuel shutoff switch

This applies to GP, XT, and RS series portable generators. 

Fuel tank draining

Verify the generator has cooled down prior to draining.

Before draining the fuel tank, place the unit in an open location away from ignition sources. Fuel must be drained into an approved gasoline-resistant container of sufficient volume. Then, remove the fuel tank cap.

Note: if you see a basket or fuel filter screen in the fuel fill opening, this can be temporarily removed.

1. Insert a siphon device into the fuel tank fill opening.
2. Insert the drain line into an approved container.
3. Operate the siphon device according to the manufacturer’s instructions.
4. Do NOT leave the device unattended while siphoning fuel.
5. Remove the siphon device from the generator. If applicable, replace the basket or fuel screen. 
6. Install and tighten the fuel tank cap onto the tank

Carburetor bowl draining

If the generator was nor previously run dry, there is likely residual gasoline left in the carburetor bowl.

Locate the carburetor behind the air filter housing. Slide a container under the carburetor.

1. With the container in place, remove the carburetor’s drain bolt using a wrench or appropriate socket and ratchet. It will be the bolt that is positioned at an angle on the carburetor’s bowl, NOT the bolt at the very bottom of the bowl.
2. Allow any remaining gas to drain into the container. Replace and tighten the screw. If a torque wrench is available, tighten to 7.5 N-m. Do not overtighten. 
3. Clean up any fuel spills.
4. Store fuel in accordance with all applicable regulations.
5. Start and run the unit until all remaining fuel has been consumed.

Portable units without a fuel shutoff switch

This includes EFI (Electronic Fuel Injector) model generators. Portable units without a fuel shutoff switch must be siphoned. This will require siphoning tools which can be purchased from an auto parts store.

Fuel tank draining

Verify the generator has cooled down prior to draining.

Before draining the fuel tank, place the unit in an open location away from ignition sources. Fuel must be drained into an approved gasoline-resistant container of sufficient volume.

 

1. Insert a siphon device into the fuel tank fill port.
2. Insert the drain line into an approved container.
3. Operate the siphon device according to the manufacturer’s instructions.
4. Do NOT leave the device unattended while siphoning fuel.
5. Remove the siphon device from the generator and install the fuel tank cap onto the tank.
6. Clean up any fuel spills.
7. Store fuel in accordance with all applicable regulations.
8. Start and run the unit until all remaining fuel has been consumed.