Small, clean cracks away from mounting points can be repaired. Long splits, cracks at tabs and cracks that spread need replacement. Look at where the crack is, how long it is and whether the cover still holds its shape.
Key takeaways
- Location matters more than length.
- Cracks at tabs usually mean replacement.
- Check the reinforcement behind the cover.
Where the crack sits
Cracks in the flat middle of the cover can be bonded. Cracks near mounting tabs weaken attachment points, and repairs there often fail.
How repair works
The plastic is cleaned, beveled and welded or bonded, reinforced on the back if needed, then sanded, primed and painted.
Signs it needs replacement
Gaps that no longer close, a cover that sags or rattles, or cracks that grow. Brittle old plastic also resists repair.
The hidden check
A crack can mean a hit that bent the reinforcement. A repaired cover on a bent bar still leaves a safety problem.
Temporary measures
Tape or zip ties help to drive to the shop, but they are not repairs.
Where plastic repair works best
Bumper covers are made of flexible plastic, usually polypropylene blends. These plastics can be welded and reinforced, but they remember their shape. A small split in the flat middle of the cover responds well. A split that runs through a curve or a corner is harder because the plastic flexes there.
A cover that is old and brittle may crack elsewhere when repaired.
What the repair should look like
A good repair begins with grinding a V along the crack, welding or bonding in filler, reinforcing the back with mesh and sanding smooth. Then it is primed and painted to match. If it needs a flexible primer, that is specified.
Ask to see the back of the repaired cover. A visible reinforcing patch means the repair was done properly. If the shop will not show you, ask why.
Get a free estimate in Santa Clara
Questions about bumper repair? Read our Bumper Repair page, call (408) 243-2530, or send photos through the estimate form. International Auto Center Body Shop, 1499 Lincoln St, Santa Clara, CA 95050. Open Monday to Friday, 8:30 AM to 5:30 PM.
Frequently asked questions
Can a bumper crack spread?
Yes, with vibration and temperature changes.
Is plastic welding durable?
When done properly, yes.
Can I drive with a cracked bumper?
If secure, short trips are fine.
Will a repaired crack show?
A good finish blends it.