Description

This series of engines are usually to be found on large walk behind rotary lawnmowers and compact ride-on mowers

They are Overhead Valve (OHV) and have their spark plug set fairly deep to the side of the rocker cover

The exhaust is on the left as viewed from behind the engine with the carburettor and air filter on the right
The plastic fuel tank wraps around the rear of the engine with the fuel cap on the right and oil dipstick at the
rear left hand corner (viewed from behind the engine).

Some have a primer for cold starting mounted to the front of the air filter base, some have ready start (automatic choke controlled by means of a thermostat mounted behind the exhaust and some have a traditional choke operated by the throttle cable.

Above the carburettor is a plastic canister which holds the air filter which is usually an oval cartridge

The Model, Type and Code numbers are stamped into the engine's pressed steel cover just above the rocker cover, or on a pressed steel plate over the exhaust.
Some have further plastic or metal top covers which may need removing or pushing up slightly in order to see them.
The Model number will begin either 11 or 12.