Summer is rapidly approaching. Is your grill primed for another season of outdoor cookouts? Oh, shoot, it still has last season’s remnants.

Now, a gas grill with cast iron grill grates is durable. It can tolerate high temperatures to give you evenly cooked food. The tough material can withstand almost everything except water. That’s where the challenge with cleaning cast iron grates starts. It’s not about keeping away scratches but rather preventing rust.

Today, I will tackle one of the most asked questions; how to clean a gas grill with cast iron grates. Let’s dive in with what you will need and how to maintain cast-iron grates.

How to Clean a Gas Grill with Cast Iron Grates

First-Time Use of Gas Grill with Cast-Iron Grates

weber grill

When you buy a new cast-iron grill, be sure to follow the manufacturer’s instructions on how to season it. I usually season cast iron cookware when I purchase them, so the same process applies to a new cast-iron grill. Properly seasoning cast iron grill grates will prevent them from developing rust.

If you’ve purchased a used grill, you’ll be able to tell from the condition of the grill grates whether it was adequately taken care of.

If there’s significant rust buildup, it’s likely the grates were not seasoned before using. Restoring cast iron grill grates in good condition is not impossible, but it’s a task that requires time and the proper equipment.

How to Clean a Gas Grill with Cast Iron Grates

How to Clean a Gas Grill with Cast Iron Grates

I cannot overstate that the best way to keep a gas grill with cast iron grill grates clean and rust-free is by cleaning the grill after each use. This will help reduce rust buildup and ensure you get tasty food every time.

Once you’ve finished cooking, turn up your gas grill on high and close the lid to allow the grill to get hot. The heat will burn off any barbecue sauce and stuck food. If you wait until the grill cools down, it will take some elbow grease to remove the stuck-on food and grease.

Once the food is burned off, turn off your gas to allow the grates to cool down to a point where you can touch the grates comfortably.

Now, use a plastic scraper and scrape the grates when still warm.

After cleaning, apply a thin coat of vegetable oil on the grates and wipe it down with a paper towel to prevent rust from developing.

If it’s been a while since you cleaned a gas grill with cast iron grates, here’s what you will need.

guy cleaning grill

Cleaning Equipment

  • Stiff bristle nylon brush/natural bristle brush or scrubber
  • Plastic scraper
  • Paper towels
  • Plastic wrap
  • Rubber gloves (optional)
  • 2 plastic buckets
  • Drying cloths

Cleaning Materials

  • Warm water
  • Dishwashing liquid
  • Vegetable oil


Step #1 Fire up the gas grill

fired up grill

Close the hood and let the grill come to full temperature. Wait for 20-30 minutes for the stuck-on food and grease to burn.

Turn off the grill and disconnect the gas line.

Step #2 Scraping

Wait for the grill to come to a warm temperature. 

With gloves on, use your trusty scraper to remove the burnt leftovers and grease. Not all of them will come off at this point.

Pro Tip:

If you don’t have a grill brush, wad up a sheet of aluminum foil into a ball, use tongs to hold and scrape the leftovers.
Remember, you don’t need to worry about scratches from wire brushes or steel wool. Any abrasive tool will do an excellent job of removing leftover food.

Step #3 Cleaning Solution

Fill a bucket with hot water and mix in with dishwashing soap.

Fill the second bucket with warm water for rinsing.

Step #4 Cleaning the Grates

Remove the grates from the grill and place them on a flat surface. I recommend placing them on a tarp or drop cloth.

Dip the brush or scrubber in the soapy solution and clean the grates thoroughly.

Rinse the grates off with warm water.

Use the cloth to dry the grates completely

Step #5 Cleaning the Rest of the Grill

  • With the plastic scraper, scrape the inside and outside of the grill to remove grease and food particles.
  • Scoop the residue or use a vacuum to suck the gunk.
  • Scrub down the grill using the brush and hot water cleaning solution.
  • Rinse every part thoroughly with warm water.

Alternatively, you can hose down the grill.

  • Follow up with drying all the parts properly with the cloth.

Step #6 Re-Assembling and Seasoning

Once the cast iron grates are clean and dry, reassemble them on the grill.

Coat the grate’s surface with vegetable oil. Spread the oil evenly with paper towels as you remove any excess oil.

Fire up the grill to medium-high, about 200 degrees Fahrenheit, for 15 minutes. This is the seasoning process. It allows the oil to bind to the cast-iron grates to create a non-stick surface and prevent rust from forming.

Repeat the seasoning process 2-3 times until you have a nice, dark color on the grates. This will tell you the grates are protected from rusting.

How to Clean Rusty Cast Iron Grill Grates

rusty grill

If you have not used your grill for a while, moisture may get in and cause the grates to become rusty. This can also happen if you don’t cover your grill.

To remove rust from cast iron grates, you have to strip down the seasoning and bring the grates back to bare metal.

Baking Soda and Lemon Juice

baking soda and lemon juice
  • Make a paste from one cup of baking soda and lemon juice.
  • Apply the paste to the rusty areas and cover with plastic wrap.
  • Wait 24 hours before scraping the rust with a stiff, natural bristle brush.
  • Wash the grates with warm, soapy water, rinse, dry and re-season.

Vinegar Soak

You will want something large enough to lay the grates flat, like a sink or large basin. In this method, let the grates soak in vinegar to remove rust.

Start by mixing equal parts of water and distilled white vinegar in a large basin or sink. Let the grates soak for an hour.

Scrub away any remaining rust with a wire brush or kitchen scrubber.

When you’ve finished scrubbing, wash with soapy water, rinse, and dry thoroughly in an oven on low heat.

Proceed with re-seasoning the grates.

Oven Cleaner


Oven cleaners contain lye. This alkaline solution will strip the cast iron grates down to the bare metal.

In this method, you need large garbage bags, oven cleaner, and gloves & safety glasses.

  • Place the grates in a well-ventilated area.
  • Spray a thin coating of oven cleaner evenly on the cooking grates.
  • Place the grates in the garbage bags and seal the bags.
  • Store the racks for a few days.
  • Once the gunk has dislodged, wash in soapy water.
  • Season the grates as we’ve instructed.

Cleaning Cast Iron Grill Grates with Vinegar


If you wonder about how to clean BBQ grill grates with vinegar, you only need white table vinegar, a spray bottle, lukewarm water, and an aluminum foil or scrubber.

  • Start by mixing two cups of vinegar and two cups of water in a spray bottle. Shake the bottle vigorously to ensure the water and vinegar mix well.
  • Spray the water/vinegar solution on the grill grates
  • Let sit for 10 minutes.
  • In the meantime, pour out the remaining water/vinegar mixture and replace it with vinegar only.
  • Fold the aluminum foil into a small square.
  • After the solution dries, spray vinegar on the aluminum foil and use it to scrub rusty surfaces.
  • Use a mild solution of warm water and dishwashing soap to rinse away food particles. Because soap will remove some of the seasoning, you still need to re-season as required.

How to Clean Cast Iron Grates with Vinegar and Baking Soda

vinegar and baking soda

A vinegar and baking soda combination is best for removing stubborn rust. This mixture gives the grates a deep clean.

  • In a plastic or metal can combine ½ cup of baking soda and one cup vinegar. Use a big dish since the vinegar and baking soda solution will bubble up.
  • Place the grates in a plastic bag and pour the solution on the grates.
  • Close the bag and leave it for 24 hours.
  • The gunk and rust will loosen and will come off easily in the kitchen sink or with a garden hose.

This method does not strip the non-stick surface.

How to Clean Cast Iron Grates Weber

dirty grill grates

Weber offers various grill grates, including stainless steel grates, cast iron, and porcelain-enameled cast iron (PECI). Grills with PECI cooking grates give you impressive sear marks on steak and heat retention, just like cast iron.

Porcelain enamel is easy to clean and maintain, unlike regular cast-iron grates. However, you need to be careful not to scratch the grates since chipped porcelain cannot be repaired.

To clean a Weber grill with porcelain cast-iron grates, you need to use a stainless-steel grill brush, preferably from Weber, to clean the cooking grates. It’s best to avoid soaps with citrus since they promote corrosion.

To remove stubborn particles, soak the grates in hot water and then use a mild dishwashing liquid together with an abrasive pad or wire brush to clean the grates. Then, use a clean cloth to dry the PECI grates.

Don’t let PECI grates air-dry. It can cause corrosion.

To clean a Weber grill with cast iron grates.

You will need kosher salt, water, and a brush.

Kosher salt has large grains; hence it’s abrasive for cleaning cast-iron grates.

Create a paste from kosher salt and water and apply it to the surface of the grates. Scrub the grates thoroughly with a nylon brush. Rinse the paste with clean water and dry with a cloth.

You don’t need to re-season the cast iron grates.


I hope the above methods for how to clean a gas grill with cast iron grates will help make this undertaking as painless as possible. A cast iron grill can serve you well for decades when you take care of it You only need to prevent rusting by seasoning the grates with a thin layer of cooking oil when food starts sticking.

Now, you can count on your cast iron grill to retain heat and give you professional-grade sear marks every time.