Non-return Valves (SLV)

Non-return Valves (SLV): One non-return valve is mounted on each cylinder head.




The Non-return valves are opened by the air pressure generated from the secondary air pump. The secondary air is led through a pipe to the secondary air ducts (integral in the cylinder heads) for distribution into the exhaust ports. There are two outlets in each exhaust port next to the exhaust valve guides.

The Non-return valves are sprung closed as soon as the secondary air pump is switched off. This prevents exhaust vapors, pressure and condensation from flowing back to the secondary air pump.