How Repair a Hole in a Fiberglass Hood

The increased demand for superior auto performance, improved aerodynamics and greater fuel economy has led to more vehicles being fitted will fiberglass parts. Auto body panels with complex contours are much easier to mold with fiberglass, and the lightweight qualities of the material place less demand on engines when the car is moving. Unfortunately, fiberglass is less resistant to impact and can be easily pierced in an impact. An effective hood repair is actually quite simple to carry out.

Removing the Hood

Open the hood and put the hood support into position to hold it open. Remove the hoses from the washer jets if there are any located on the hood. Use a socket and ratchet to undo the bolts that hold the hood onto the hinges, using the help of a second person to carry the weight.

Sanding the Hood

Place the hood on a flat working surface so the top is facing upward. Pull away flaking fiberglass by hand before wrapping a sheet of P80-grit sandpaper around a rubber sanding block. Lightly sand around the edges of the hole until all of the sharp edges have been removed. Turn the hood upside-down and repeat the process on the inside.

Applying the Matting

Cut out a sheet of fiberglass matting that is approximately two inches larger in circumference than the actual hole itself. Apply fiberglass resin to the surface of inner hood with a paintbrush and lay the matting over the hole, making sure it is tightly pulled and bonded around the edges. Apply two additional coats of resin over the fiberglass matting to harden it and fix it to the panel.

Adding Fiberglass Paste

Turn the hood back over so the top is facing upward. Mix a small quantity of fiberglass paste with hardener and use a plastic spreader to smear the paste into the hole so it rests against the dried matting on the opposite side. Make sure a small amount of fiberglass paste sits above the surface of the hole and spread it out evenly so it integrates into the existing paintwork. Leave it to harden.

Rubbing Down

Rub down the hardened fiberglass with P80-grit sanding paper until it is flush with the surface of the hood. Use compressed air to blow away excess dust and mix a small quantity of body filler with hardener. Spread the activated body filler over the repair to cover pinholes in the fiberglass paste and leave to dry before rubbing down to a smooth finish with P180-grit sanding paper.