1977 Volvo 262 264 265
Air Injection Reactor System
This system admits fresh air to the hot exhaust gases in the exhaust manifold. The fresh air will burn the
unburned portion of the exhaust gases to reduce hydrocarbon and carbon monoxide contents.
The air pump is located at the engine front and driven by a belt.
The air is drawn into the air pump via an air filter. The compressed air is fed out of the pump through the
diverter valve. This valve has two functions. It regulates the air pump pressure. It also shuts off the air
delivery when using the engine to brake. If the system was allowed to operate under this condition, fresh
air mixed with the overly rich vapor would cause a backfire.
The backfire valve admits air into the exhaust manifold but prevents return of exhaust gas to the air
pump incase of a backfire or air pump malfunction, such as drive belt damage.
Air Injection Reactor check
This system should be checked every 15,000 miles. Hoses and connections should be checked for leaks
and condition. Check the diverter valve and backfire valve operation. Check the operation of the air
pump and that there is no excessive noise.
The exhaust emissions will be incorrect if the AIR System does not operate properly.
Catalytic Converter
This is a supplementary device in the exhaust system, designed to clean the remaining dirty exhaust
gases.
This device is mainly a container with a ceramic material insert, designed to let the exhaust gases pass
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