MotoRad MGC791 Locking Fuel Cap – Vented Screw-On Gas Cap

Protect your fuel from theft and vandalism with the MotoRad MGC791 Locking Fuel Cap. Designed as a direct-replacement locking gas cap for thousands of vehicle applications, the MGC791 combines a secure keyed locking mechanism with the proper pressure and vacuum relief required by modern evaporative emissions systems.

The MotoRad MGC791 is a vented, screw-on fuel cap manufactured from durable automotive-grade materials and designed to meet state and federal emissions requirements.

Features

• Keyed locking fuel / gas cap

• Helps protect against fuel theft and vandalism

• Vented design

• Screw-on installation

• Integrated ratcheting system promotes positive closure

• Specifically designed pressure and vacuum relief valves

• Helps prevent fuel vapor leakage and evaporation

• Designed to meet state and federal emissions requirements

• Independently tested for emissions control

• Manufactured from durable, long-life materials

• Can be used in either the locked or unlocked position

• Black finish

• MotoRad part number MGC791

Broad Vehicle Compatibility

The MotoRad MGC791 is a multi-vehicle locking fuel cap rather than an FJ Cruiser-specific product.

MotoRad catalogs the MGC791 for thousands of vehicle applications across numerous makes and models, including select:

• Toyota

• Lexus

• Ford

• Chevrolet

• GMC

• Honda

• Nissan

• Mazda

• Subaru

• Volkswagen

• Volvo

• Jeep

• Chrysler

• Dodge

• And many others

Because fitment varies by year, make, model and engine, verify that MotoRad MGC791 is listed for your specific vehicle before ordering.

Toyota FJ Cruiser Application

The MGC791 has been used as a locking fuel cap option for the Toyota FJ Cruiser, providing an alternative to the factory non-locking gas cap.

For FJ Cruiser owners, a locking fuel cap can be particularly useful for vehicles used for:

• Daily driving

• Overlanding

• Camping

• Extended road trips

• Public or long-term parking

• Off-road travel

Always verify exact year and vehicle fitment before ordering.

Locking or Non-Locking Operation

One convenient feature of the MotoRad MGC791 is the ability to use the cap in either a locked or unlocked configuration.

To lock the cap:

1. Install the cap by turning it clockwise until it clicks or reaches its stop.

2. While holding the cap, insert the key.

3. Turn the key clockwise approximately one-half turn.

4. Remove the key.

When properly locked, the outer portion of the cap will spin freely, preventing the cap from being unscrewed.

If you don't want to lock the cap, it can also be operated in its unlocked position for normal everyday use.

Emissions-System Function

A fuel cap does more than simply cover the fuel filler opening.

The MGC791 incorporates specifically designed pressure and vacuum relief valves to properly seal and vent the fuel system. A properly functioning fuel cap helps prevent fuel vapor from escaping through the filler neck and supports proper operation of the vehicle's evaporative emissions system.

A missing, loose or improperly sealing gas cap can potentially contribute to an EVAP-related warning or Check Engine light on compatible vehicles.

Specifications

Manufacturer: MotoRad
Part Number: MGC791
Product Type: Locking Fuel Tank Cap
Locking: Yes
Vented: Yes
Cam Type: Screw-On
Thread Diameter: 1.563"
Shape: Round
Color: Black
Tethered: No
Indicator Markings: Yes
Grade: Standard Replacement
Materials: Plastic, Metal & Rubber

Interchange / Cross-Reference Numbers

MotoRad lists numerous interchange numbers for the MGC791, including:

• ACDelco GT139L

• Gates 31778

• Gates 31780

• Stant 10501

• Stant 10504

• Stant 10507

• Stant 10591

• NAPA 703-1689

• Duralast / AutoZone 5791

Cross-reference numbers are provided as a shopping aid. Always verify vehicle fitment before ordering.

Frequently Asked Questions

What is the MotoRad MGC791?
The MGC791 is a keyed locking, vented, screw-on replacement fuel cap designed for thousands of automotive applications.

Does the MGC791 fit the Toyota FJ Cruiser?
The MGC791 has been sold as a locking fuel cap application for the Toyota FJ Cruiser. Verify your specific model year against current MotoRad fitment data before ordering.

Can I use the cap without locking it?
Yes. One advantage of the MotoRad locking cap design is that it can be operated in either the locked or unlocked position.

Is the MGC791 vented?
Yes. MotoRad specifies the MGC791 as a vented fuel cap with pressure and vacuum relief provisions.

Can the wrong gas cap cause a Check Engine light?
Yes. A fuel cap that does not properly seal or vent for the vehicle's EVAP system can potentially trigger an emissions-related warning or Check Engine light.

Does the cap include keys?
The MGC791 is a keyed locking fuel cap. The locking keys are supplied with the cap.

Is this only for Toyota vehicles?
No. MotoRad catalogs MGC791 for thousands of applications across many vehicle manufacturers. Always verify the exact year, make, model and engine before ordering.