If you have an old engine that simply won’t move, learning how to unstick a piston from an old car can not only save you tons of money, but it can also give you a valuable skill you can use in the future. Exposure to rust and lack of use can cause the pistons of an old engine to become stuck, requiring quite a bit of effort to free them up. With this guide, you’ll learn how to get a stuck piston moving again without having to resort to drastic measures.
What you’ll need:
- Penetrating fluid
- Apply penetrating fluid to the stuck piston. There are different types of petroleum-based fluids you can try, ranging from fuel oil and kerosene to dedicated penetrating fluids such as Liquid Wrench and PB Blaster. In some cases, you can even use automatic transmission fluid. As long as the fluid has some sort of lubricating properties, it can be used to unstick a piston.
- Wait a while. It may take a few hours, days or even weeks for the fluid to soak in. Check on the engine regularly to see how the process is going.
- Attempt to free the piston. Lightly tap or wiggle on the piston to free it bit by bit. At some point, the piston will begin moving enough for you to clean the piston walls. When the piston is free, observe it and the piston walls for rust, grime or any other contaminants or damage that could otherwise interfere with piston movement.