How to stop and repair a transformer oil leak

Learn how to repair a transformer oil leak with Belzona products. Belzona1212 is a two-part surface-tolerant epoxy composite engineered specifically for in-situ application to wet, oil contaminated and underwater surfaces.

This multi-purpose solvent-free material exhibits rapid cure and excellent adhesion to manually prepared substrates, where grit blasting cannot be achieved. For this repair, we will need Belzona 9611, Belzona 1212, Belzona 9341, and a few hands and mechanical tools.

With Belzona cold-applied materials the repair is easy and does not require specialist tools. To stop the leak, we use Belzona 9611 – a rapid curing putty designed for sealing low pressure live leaks. Belzona 9611 is used in combination with Belzona metal systems to create permanent repairs.

Step-by-step instructions

1. Wipe off excess leaking material and roughen the surface by deeply scoring or grinding

2. Measure and cut off the required amount of Belzona 9611 and knead it in gloved hands until a uniform grey color is achieved

3. Using a Belzona applicator, press the mixed material into the damaged area and apply pressure until the product has hardened

4. After approximately one hour remove the applicator

5. Using a mechanical grinder, abrade the hardened material and the substrate. Remove all the contaminants and residue with a cleaner/degreaser

6. Delimit the area with a masking tape

7. Measure equal amounts of Belzona 1212 Base and Solidifier. Thoroughly mix the product until uniformly mixed

8. Take a pre-cut piece of Belzona 9341 Reinforcement Tape and wet it out with the mixed material

9. Then, apply Belzona 1212 onto the substrate using a short-bristled brush, working the material well into the surface

10. Immediately, embed the wetted-out reinforcement tape into the applied material and encapsulate it with another layer of Belzona 1212

11. Remove the masking tape

12. The Application is now complete!

For more information about Belzona 1212, its properties, benefits, and applications, visit: Belzona 1212

Frequently asked questions

Yes. Rezitech uses Belzona 9611 and Belzona 1212 to perform live leak sealing on low-pressure transformer oil leaks without the need for hot work or extensive downtime. Belzona 9611 rapidly seals the active leak, while Belzona 1212 provides a durable long-term repair even on wet and oil-contaminated surfaces. This cold-applied repair method minimises operational disruption and improves safety compared to traditional welding repairs.

Belzona 1212 is specifically engineered for in-situ repairs on wet, oily, and difficult-to-prepare surfaces commonly found on leaking transformers. The material offers excellent adhesion without requiring abrasive blasting, making it ideal for confined or live operating environments. Its rapid curing properties and solvent-free formulation allow Rezitech technicians to complete reliable repairs quickly and safely.

Belzona1212, a two-part surface-tolerant epoxy composite engineered specifically for in-situ application to wet, oil contaminated is the best epoxy to repair a transformer leak.

Rezitech transformer leak repairs typically utilise Belzona 9611, Belzona 1212, and Belzona 9341 alongside standard mechanical hand tools. Belzona 9611 is used first to immediately stop low-pressure leaks, while Belzona 1212 and reinforcing materials such as Belzona 9341 create a strong, permanent composite repair system. Because the materials are cold-applied, no specialist welding or heat-based equipment is required.

Belzona 9611

CASE STUDY

transformer oil leak repair

TRANSFORMER OIL LEAK REPAIR

Repair of transformer tank and inspection cover oil leaks

Any Questions?

Fill out the form below and we’ll get back to you as soon as possible.