Will Silicone Repair a Leak in a Plastic Radiator?

Silcone sealant can repair a leak in a plastic radiator, but only temporarily.

Silicone sealant has long been used as a way to heal cracks in metal radiators because of its ability to adhere to the metal and withstand high heat. It does not work as well with plastic radiators.

Purpose

Plastic radiators in cars have been around since the 1980s as a cheaper alternative to the standard metal radiators. It also handles the heat and high pressure better as well. Silicone sealant is used to fill cracks and holes in various objects. Silicone sealant works well with metal radiators and can seal a small leak.

Considerations

Silicone sealant will temporarily fix a leak in a plastic radiator, but the high pressure will eventually erode and degrade the sealant, causing the leak to return. If you need an emergency repair, silicone sealant will work.

Solution

The only real solution to permanently fixing a leak in a plastic radiator is to weld another plastic, such as nylon, into the crack. The melted plastic will bond to the plastic in the radiator creating a seal that will last.

References

• Urethane Supply.com: Fixing A Plastic Radiator
• Caparadiator.com: Plastic Radiators
• Radiator.com: How To Fix A Radiator Leak