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Welcome to Mainline Diesel

Established in 1989, Mainline Diesel Engineering is a provider of diesel engine services based 30 minutes south of Brisbane in Australia. Mainline is a privately owned & family run business. Business principal, Kevin Riley, served 13 years at L. Gardner & Sons factory in Manchester, UK where he became a fully skilled diesel fitter building and testing Gardner diesel engines. Since that time, Kevin has gained more than 30 years experience on Gardner engines within the Australian marine industry.

Excellence in Service

Mainline is committed to serving customers well and takes pride in having a thorough knowledge and understanding of the Gardner product.  Customer enquiries are handled politely, with respect and in a timely manner. 


In 2014, Mainline proudly celebrates 25 years of professional service to the Gardner engine community in Australia and worldwide. And carrying a comprehensive stock of new, reconditioned and second hand Gardner parts in Australia and with specialised Gardner tooling and equipment, Mainline has the ability to service & supply all your Gardner engine needs anywhere in the world in a professional & prompt manner.

The range of services offered includes:

-  Door to Door Export Service
-  Bespoke reconditioned Gardner engines
-  Supply of genuine Gardner parts
-  Specialised Gardner fuel injection service
-  In-house engine reconditioning
-  On site service, overseas travel


- NEW Advance gearboxes for marine use
- Lister engine service, repairs & reconditioning