A high-quality coolant expansion tank, designed for JCB machines with Perkins AR and AK engines. It is a key component of the cooling system, serving as a reservoir for the coolant that expands with temperature. It ensures the correct fluid level in the system and allows for its inspection. Made of durable plastic resistant to high temperatures and pressure, it guarantees a leak-proof seal and long service life.
GX-AFTER is the smart choice for your machine. We provide high-class replacement parts that combine excellent quality with an attractive price. Each part is carefully verified to ensure full compatibility and reliability you can depend on.
| Brand (Machine Type) | Model |
|---|---|
| JCB (Backhoe Loaders) | 3CX, 4CX (with Perkins AR, AK engines) |
The list above is for reference. Before purchasing, we recommend a visual comparison with your old part.
Before replacing the tank, ensure the engine is completely cool. Opening the cap on a hot cooling system can cause a violent spray of hot coolant and steam under high pressure, which can cause severe burns.
The expansion tank compensates for changes in coolant volume and maintains the correct pressure in the system. If it is damaged, it leads to leaks, air in the system, and consequently to engine overheating.
A cracked expansion tank is a direct path to an overheated engine.
Even a small coolant leak leads to air entering the system and a loss of cooling efficiency. The cost of replacing the tank is negligible compared to an overhaul of an overheated engine. Don't take risks – order a new, durable GX-AFTER tank and ensure safe operating conditions for your engine.
📞 Can't find the part you're looking for?
No problem. Our website shows only a few thousand of the over 60,000 parts we have in stock. Contact us – we probably have what you need on the shelf!
The most common cause is material fatigue from thousands of heating and cooling cycles, which leads to the plastic losing its flexibility. Another cause can be excessive pressure in the cooling system, e.g., due to a faulty head gasket or a malfunctioning cap.
2. What is the role of the expansion tank cap?The cap is not just a "plug." It has two valves: a pressure valve that releases excess pressure as the fluid heats up, and a vacuum valve that allows air to enter the system as the fluid cools. A faulty cap can lead to burst hoses or the expansion tank itself.
3. My old tank is brown inside. Is that normal?A brown deposit inside the tank is usually rust and scale from the entire cooling system. This indicates the use of old coolant or water. When replacing the tank, it is recommended to thoroughly flush the entire system and fill it with a new, high-quality coolant.
🛡️
Engine Protection
Prevents overheating and costly failures.
🎯
System Integrity
Eliminates leaks and prevents air in the system.
📦
High Durability
Material resistant to pressure and high temperature.
Have doubts or need confirmation to avoid costly downtime? Call us. Our experts will help you choose the right part to get your equipment back to work as soon as possible.
Data sheet
Specific References
Manufacturer
Responsible person
See also similar products






Expansion tank suitable for JCB 3CX 4CX backhoe loaders with AR AK engine.

















