After extended service the cooling system will slowly lose efficiency, due to the build-up of scale,
deposits from the water and other foreign matter which will adhere to the internal surfaces of the radiator and water channels.
This will be particularly so if distilled water has not been used at all times.
Removal of the deposits can be carried out easily, using a suitable flushing agent in the following manner.
After allowing the cooling system to drain, replace the drain plug and refill the system with clean
water and a quantity of flushing agent. Any proprietary flushing agent in either liquid or dry form may be used, provided
that it is recommended for use with aluminium engines. Never use a compound suitable for iron engines as it will react
violently with the aluminium alloy. The manufacturer of the flushing agent will give instructions as to the quantity to be used.
Run the engine for ten minutes at operating temperature and drain the system. Repeat the procedure
twice and then again using only clean cold water. Finally, refill the system as described in the next section.