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How Do You Fix A Rusted Mower Deck?

How Do You Fix A Rusted Mower Deck

Lawn maintenance professionals may encounter rusty mower decks. That's annoying. How to fix a rusted mower deck We've learned how to replace a corroded mower deck.

We've tried good, awful, and ugly. We'll show how to fix a rusted mower deck without the "ugly" way (with a step-by-step guide).

A rusty mower deck shouldn't be thrown away. Fixable. Most rusty mower decks can be repaired without a mechanic. Before using fiberglass and epoxy, decide if repairing the corroded mower deck is worth it.

Identifying the problem (how to find it)

You must determine if the damaged region is structural, like an engine mount, or non-structural, like a deck hole. Mower deck rust is a regular concern. If the wheels are gone and the engine is still running, your mower deck is probably kaput. Here's how to replace a corroded mower deck hole.

A Tool List for Fixing Rusted Lawn Mower Decks

Let's go over how to fix a rusted mower deck now that you have the right tools. The following is a process overview and a checklist for setting up your workstation.

Fiberglass applications may be familiar. If you're like me, you may need some guidance to fix the rusted mower deck. This instruction will help you repair a rusty mower deck.

1.Prepping the Workspace

First, prepare your workstation. There must be adequate room to work on both the top and bottom of the deck at the same time.

Pull out your workbench or table to create more space. This can be a garage, driveway, or yard corner. Don't put it in the kitchen or lounge to make your partner pleased.

You'll need help lifting the mower onto the bench or table; I'd offer a neighbor a beer. Before the repair, the mower must be properly positioned. To access the underside, tilt the deck.

Deck support options include jack stands and paint cans. Ensure the mower won't roll. The resin cures quickly once activated, so don't lose time searching.

2. Make sure the area where you're working is well ventilated.

Resin creates deadly fumes if you've ever worked with it. Always keep your desk well ventilated. Most don't have an extraction system, so open the windows. Outdoor work is possible. 

3. Remove the rusted areas.

When doing repairs, make sure you have your protective gear. Wear gloves, a face mask, and eye protection.

Wire-brush the mower deck before repairing the rust. Removing dirt and grass from the deck helps remove rust.

4. Straightening Things Up

Use a hammer to knock off rust and rusty spots. Here, you'll clean up what the wire brush missed.

5. Remove any corroded metalwork.

Move on to the rest of the deck (the completely rusted ones) after wire brushing and hammering the salvageable pieces.Remove all rust and leave unoxidized metal.

Rusted portions must be removed to create a hard surface. Start by eliminating rust using a grinder or metal file. Repeat steps 3 through 5 slowly and with the right tool.

6. Use anti-rust paint.

Apply rust-inhibiting paint to the repaired areas. Wait 10 minutes between coats. Rust is transformed to Iron Tannate using Tannic Acid and Organic Polymer inhibitors. Stable material means you won't miss spots.

7. Cut the glass matting to size.

Fiberglass matting is next. Cut the matting into patches with scissors. Two inches of overlap is recommended. If the hole is 6 inches wide, cut the mat to 10 inches wide with a 2-inch overlap.

After epoxied, it gives me around 1/4-inch thickness overall, so prepare 8 pieces for your rusted mower deck repair. Once cut, save the pieces for later.

8. Combine the resin and Activator.

Ready to mix resin and activator? Please prepare the application area by completing steps 1–7. Grab your resin, hardener/activator, mixing container, measuring cup, and mixing stick. Mix per manufacturer's instructions.

9. Apply the glass mat.

Apply mixed resin with a paintbrush to your mower deck to fix the rusty section. Install precut glass matting. Then, put on another layer of epoxy. Apply epoxy liberally.

If possible, alternate exterior and interior matting. Apply eight pieces of matting, then a final layer of epoxy. Now you may let it heal.

10. Sand the resin back to a keyed surface.

After the epoxy cures, sand. To assure paint adhesion, lightly sand fiberglass. Use 80-grit sandpaper. Fiberglass should be bland.

11. Paint the Finishing Touches

Apply finishing paint outside. I hope you picked a comparable shade. I propose using two-part epoxy and high-durability paint to preserve the underside. It's more expensive, but it prevents mower deck corrosion.

Other Repair Options for Your Mower Deck

There are additional things to consider when replacing a rusted mower deck. For small holes, like a penny, replace the fiberglass with 2-part epoxy metal putty to attach rusted mower decks.

  • Remove steps 7 through 9 from my step-by-step guide and replace them with my putty approach:
  • Mix the 2-part epoxy putty according to the manufacturer's instructions.
  • Apply putty to the required area.
  • Allow the putty to partially pass through the hole by applying pressure.
  • By applying pressure on either side of the repair, the putty will hold itself in place.
  • Allow for curing before proceeding to step 10.

Metal patching may be needed to fix a rusty mower deck that is too large for fiberglass, such as a commercial deck. Welders, metal cutters, rivet guns, and repair metal will be needed.

Again, steps 7 through 9 can be metalworking. This approach isn't recommended for a tiny walk-behind mower because the metal is thinner and may not be weldable.


Grass is cut by the mower deck. The deck is metal and plastic. Make sure your mower deck doesn't corrode.

How to prevent mower deck rust. Wash it with soap and water, let it dry, then apply anti-rust spray or liquid. Before applying a protective coating, use paint thinner to eliminate rust.