DIESEL INJECTION 0116 276 6831 MOTOR CO 0116 276 7092 
info@welhamgroup.co.uk
When it comes to iconic British diesel engines, the Leyland TL11 stands out as a real workhorse. Developed to power some of the most recognisable lorries and buses from the 1970s through to the 1990s, this 11.1-litre, six-cylinder turbocharged engine earned its reputation for reliability and pulling power. But at the centre of its performance lies one crucial component — the fuel injection pump.
The Unsung Hero: Fuel Injection Pumps
In a diesel engine, the fuel injection pump is arguably the most critical part of the combustion process. Unlike petrol engines, where air and fuel are mixed before entering the cylinders, diesel engines depend on high-pressure, precisely timed delivery of fuel directly into the combustion chamber.
The TL11 typically used CAV (Lucas) inline or rotary-type fuel injection pumps, known for their mechanical reliability and ease of servicing. The example shown in the image above is a refurbished CAV-style injection pump, expertly rebuilt by Majormec, a UK-based specialist in diesel injection systems.
When it comes to iconic British diesel engines, the Leyland TL11 stands out as a real workhorse. Developed to power some of the most recognisable lorries and buses from the 1970s through to the 1990s, this 11.1-litre, six-cylinder turbocharged engine earned its reputation for reliability and pulling power. But at the centre of its performance lies one crucial component — the fuel injection pump.
The Unsung Hero: Fuel Injection Pumps
In a diesel engine, the fuel injection pump is arguably the most critical part of the combustion process. Unlike petrol engines, where air and fuel are mixed before entering the cylinders, diesel engines depend on high-pressure, precisely timed delivery of fuel directly into the combustion chamber.
The TL11 typically used CAV (Lucas) inline or rotary-type fuel injection pumps, known for their mechanical reliability and ease of servicing. The example shown in the image above is a refurbished CAV-style injection pump, expertly rebuilt by Majormec, a UK-based specialist in diesel injection systems.
Key Features of the CAV Injection Pump:
- Mechanical Operation: Fully mechanical — no electronics to go wrong, making it ideal for heavy-duty use and field repairs.
- Inline or Rotary Configurations: The TL11 often featured inline pumps for greater fuel delivery and performance, especially in turbocharged setups.
- Adjustability: Parameters like timing and fuelling can be fine-tuned — essential for commercial vehicles under varying loads.
- Common Applications: Leyland Leopard and Tiger buses, military vehicles, and a variety of haulage trucks across Britain and abroad.
Majormec: Keeping the Classics Running
The pump in question bears the “MAJORMEC” and “CAV ENGLAND” markings, indicating it’s a genuine reconditioned unit — not an aftermarket copy. Companies like Majormec play a crucial role in preserving diesel heritage, supplying parts for fleets still in service or under restoration.
Why It Still Matters
While modern engines have moved on to electronic fuel injection and common-rail technology, there’s still strong demand for these rugged, fully mechanical systems. Their simplicity, durability, and ease of maintenance make them invaluable in rural operations, developing countries, and among enthusiasts restoring vintage machinery.
Final Thoughts
The Leyland TL11’s fuel injection pump is more than just a piece of engineering — it’s a symbol of British mechanical ingenuity. Thanks to specialists like Majormec, these classic diesel engines can continue to perform reliably for years to come, whether they’re hauling goods, transporting passengers, or simply being enjoyed by enthusiasts.
Welhams: Restoring Function and Reliability
The unit pictured bears the hallmark of expert craftsmanship by Welhams, who have reconditioned this fuel injection pump ready to go to it’s home in Surrey! If you have a job you’d like to discuss with us, you can get in touch with Chris or one of the Diesel team by choosing option 2 when you ring us on 0116 276 6831.
Importance of Quality Diesel Fuel Injectors
Using high-quality diesel fuel injectors is crucial for maintaining optimal engine performance and reliability. Low-quality or counterfeit diesel fuel injectors can lead to poor fuel atomisation, increased wear and tear on the engine, and potential damage. Investing in genuine or reputable diesel fuel injectors ensures long-lasting performance and minimises the risk of engine problems.
Diesel fuel injectors are vital for the proper functioning of diesel engines. They ensure precise fuel delivery, combustion efficiency, and overall performance. Regular fuel injection service and proper diagnosis of diesel fuel injectors are essential for maintaining their performance.
Choosing high-quality fuel injectors also plays a crucial role in ensuring the longevity and reliability of your diesel engine.
If you need help with the repair of your diesel fuel injectors, contact Welham Group to find out how we can help you.