Lister Petter - Engine Ranges

Engine Ranges

One of the most popular early Petter engines was the AVA series, AVA1 and AVA2 (1- and 2-cylinder engines respectively), and the Lister D. The majority of these engines were hand-crank start and fully mechanical, without any electronics or electrical controls. Engines like this, if not still working, are now considered collectors' pieces.

Widely used examples of later models include the LT series, often used in single-cylinder form to power small cement mixers, and the ST series, a popular engine for canal boats. They too were large and heavy engines with low power outputs, low operating speeds and extremely robust construction, capable of reliable operation for years even under the conditions of abuse and neglect of maintenance found in their typical construction-site applications.

A particularly successful model was the A range; these engines were much smaller and lighter than earlier models, although still extremely robustly constructed. Plant powered by an A-range engine is often light enough to be lifted and carried by two workers, instead of requiring a wheeled chassis, which is a great advantage on a construction site. The A range is particularly suitable for powering small generators of around 4-5kVA output. Unlike earlier designs it is capable of running at up to 3600 rpm and can therefore generate mains-frequency AC using a two-pole alternator; the lower operating speed of earlier designs mandates the use of a four-pole alternator, which is much larger and heavier for the same output power.

In the writers opinion the Petter A range can be problematic especially in the raw water cooled marine version known as the Petter Mini-6. The problem is that the aluminium heads corrode rather badly in salt water and head gaskets are rather troublesome. Frequently water will leak out of the engine into the boat. Special head nuts can be obtained that will allow a slightly higher torque to be used and special high temperature black RTV silicon sealant can be used on the water jacket. If possible use a genuine Petter gasket (old type that has asbestos reinforcement) In jellyfish infested waters a large basket type water strainer and an engine overheat alarm are must-haves as without these items one can easily have an engine fire (the rubber exhaust hose catches fire and the silencer melts) After an engine fire the head gasket WILL need replacing. There was also a freshwater cooled Petter Mini-6 that was made for Westerbeke but these are extremely rare in Europe. The good points about the Mini-6 are its compact size and low weight (it is smaller than the Japanese market leader and it can be used to replace petrol engines without overloading the boat) If the Japanese engine will not fit one can replace the Petter with the Farryman Yellow River Star, however the cost is quite considerable. Another solution is to change the cylinder barrel and head for the highly reliable air cooled versions but this fairly popular method is more suitable for an open boat or workboat. Some marine Mini-6 engines were air cooled from the factory.