Radiators are important heating and cooling systems present in many homes, vehicles and even in some electronics. If a radiator springs a leak, it will function at lesser capacity, if it functions at all. Repairing such leaks and seals need not be terribly difficult (in fact, there are plenty of online tutorials); however, the material used to seal a radiator will determine how long it will continue to work. One of the most versatile materials you can use to seal a radiator is silicone, which is available in a variety of forms, such as sealant, tape and epoxy.
Locate the Leak
Before you can seal your radiator, you will have to determine where there is a leak, or if no leak exists, which seal you would like to replace. Silicone seals last much longer than rubber ones, so in the latter instance, you should consider upgrading to a silicone seal like Silastic. If you are looking for a leak in a car, check the radiator itself, followed by the hoses and their connections to the engine. On a radiator in the home, look at the unit itself, the valves and the pipe couplings.
Patch the Radiator
If you find out that the leak is coming from the radiator unit, you've got a couple of options. You can choose to use a high-heat silicone sealant to gum up the hole through which your radiator leaks. Silicone sealant is excellent, because it will expand to fit the hole and harden, and will withstand a great deal of heat. Another option is to use silicone tape such as Rescue Tape. After wrapping the tape around the area that is leaking, silicone tape will fuse to the area and create a permanent and rather flexible seal.
On a home radiator, tightening the nut of the coupling will often solve a radiator leak. If this does not work, however, the "olive," which seals the pipe to the radiator, may need to be treated. Applying a silicone sealant coating to the olive will often work, or you can wrap a small piece of high-temperature silicone tape around it. In a vehicle, bad hoses and petcock valves can be treated similarly. Unfortunately, if your car's radiator is leaking and you determine that the engine is the issue, no amount of silicone will be able to repair the leak. You will need to take your car to a mechanic to ensure that the leak is dealt with by professionals.