Having a hairline crack in your toilet bowl or tank can be annoying and lead to leaks or other problems. Thankfully, hairline cracks are relatively easy to fix yourself with just a few steps and supplies. Here is a detailed guide on how to fix a hairline crack in a toilet bowl or tank.
Inspecting the Crack
The first step is to inspect the crack closely to determine the exact location, size, and severity.
- Carefully examine the exterior of the toilet bowl and tank. Hairline cracks are thin fissures that may be difficult to see at first glance.
- Look for any crack lines, especially near the base of the bowl or corners of the tank.
- Check the underside of the tank as well since cracks often occur here.
- Use a flashlight to illuminate the area and highlight any cracks present.
Once you’ve identified the location of the crack, assess the length and thickness. Take note if the crack is leaking water or if it appears to go all the way through the porcelain. This will determine the repairs needed.
Cleaning and Drying
Before applying any adhesive, thoroughly clean and dry the area around the crack:
- Clean the crack and surrounding area with a stiff nylon brush and abrasive cleaner to remove any dirt, hard water deposits, or residue.
- Rinse the area well and let it fully air dry. Use a hairdryer on a cool setting to speed up drying time if needed.
- Make sure the porcelain is completely dry for the best adhesion with the epoxy. Any moisture will prevent proper bonding.
Proper cleaning and drying provides the optimal surface for the adhesive to grab onto.
Applying Epoxy
For small hairline cracks, a two-part porcelain repair epoxy is the best solution. When mixed, the epoxy hardens to the same strength and color as the original porcelain. Here are the steps for application:
- Select a two-part epoxy made specifically for porcelain repair. Products like PermaFix or Polene Epoxy Putty are good options.
- Mix the epoxy resin and hardener together according to package directions. Only mix as much as you can use within the working time.
- Using a putty knife, press the mixed epoxy firmly into the crack, filling it completely.
- Push additional epoxy over the crack and feather the edges for a smooth finish.
- Remove any excess so it’s flush with the toilet surface.
- Allow the epoxy to fully cure based on the product directions, usually 24-48 hours.
The epoxy will bond tightly within the crack for a permanent seal. Be sure to read all safety precautions before use.
Replacing Tank Bolts
If the hairline crack is located on the tank bolts or bolt holes, replacement is needed.
- Turn off the water supply and flush the toilet to empty the tank. Sponge out any remaining water.
- Use a ratchet wrench to loosen and remove the tank nuts from the cracked bolts.
- Apply plumber’s putty or silicone caulk to the new brass bolts and insert them through the tank holes.
- Reinstall the washers and nuts and evenly tighten by hand, then finish with a wrench. Do not over tighten.
- Let the plumber’s putty or caulk fully set for at least 2 hours before turning the water back on.
This will securely fasten the tank back down, preventing leaks from cracked bolts.
Patching Kits and Sealants
For more severe cracks and leaks, full porcelain patching kits can provide a permanent seal.
- Clean and dry the area thoroughly and roughen the porcelain with sandpaper for better adhesion.
- Mix and apply the adhesive paste according to kit instructions and smooth over the crack using the putty knife or spatula provided.
- Allow full curing time based on product directions. The patch will harden to match the existing surface.
- Caulk or flexible sealant can also seal cracks and prevent water leaks. Be sure to only apply to clean, dry surfaces.
These patching solutions allow you to repair damaged areas for a long-lasting fix.
When to Call a Professional
While many hairline cracks and fractures can be repaired at home, it’s best to call a plumber for:
- Cracks wider than 1/8th inch or deeper than the glaze. These may indicate more severe underlying damage.
- Signs the hairline crack is spreading or new fractures are forming.
- Inability to fully stop the leak using epoxy or sealants.
- Cracks located within the water tank itself. The tank will likely need replacing.
- If you are uncomfortable performing the repairs yourself.
For complex cracks or extensive damage, a professional plumber has specialized tools, materials, and expertise to properly assess and fix issues for the long run.
Preventing Future Cracks
To help avoid hairline cracks in the future:
- Avoid exposing the toilet to sudden temperature changes which can create thermal stress. Open a window or door to moderate the temperature.
- Install a toilet tank insulation kit to prevent condensation and corrosion.
- Use a toilet tank disinfectant to keep the tank and bolt holes clean and free of chemicals.
- Ensure the floor is level beneath the toilet to prevent uneven stress.
- Be gentle when tightening the tank bolts to avoid cracking the porcelain.
With proper care and maintenance, you can help prevent hairline cracks from developing in your toilet. But even if they do occur, the right repairs will have your toilet restored and back to normal with minimal effort.
FAQs
What is the easiest way to fix a hairline crack in a toilet?
For small cracks, applying a two-part porcelain repair epoxy that hardens to the same strength as the original porcelain is the easiest permanent solution. The epoxy bonds tightly within the crack for a seamless fix.
How do you fix a hairline crack in a toilet tank?
Clean the area thoroughly, make sure it’s completely dry, and apply a porcelain repair epoxy. For cracks around tank bolts, replace the bolts with new ones and use plumber’s putty or caulk during reinstallation. This will seal the area and prevent leaks.
What kind of adhesive works best for hairline cracks?
A two-part porcelain repair epoxy designed specifically for bonding to porcelain provides the strongest, most long-lasting repair for hairline cracks. Products like PermaFix and Polene Epoxy Putty are great options.
Should I replace my toilet if it has a hairline crack?
Most small hairline cracks can be repaired rather than requiring full toilet replacement. Unless the crack is severely damaged or spreading, an epoxy or sealant application should stop any leaking and restore the appearance.
Can you use JB Weld on a cracked toilet?
JB Weld can work for some toilet repairs but is not ideal for hairline cracks. A porcelain-specific epoxy like PermaFix will provide much stronger adhesion and hold up better to the temperature changes and moisture exposure toilets experience.
Conclusion
Hairline cracks in a toilet bowl or tank can develop over time but are often simple to fix with the right materials and techniques. After thoroughly cleaning and drying the area, applying porcelain repair epoxy or sealant provides a long-lasting repair that blocks leaks and matches the original appearance. For recurring issues or larger cracks, seeking professional assistance may be needed. With some basic DIY skills and supplies, minor hairline cracks can be fixed yourself, saving the hassle and expense of replacing the entire toilet. Being attentive to any small fractures as they develop allows you to seal them before major damage occurs.
