Injection engines are equipped with injectors with which the air/petrol mixture is injected into the combustion chambers. When replacing or cleaning the injectors, you cannot reuse the rubbers that provide the seal, their replacement is the only option. Many injection problems are due to worn injector seals.
The small joints are for the inner side and the larger ones for outer side. It is recommended to replace the inner and outer seals at the same time, you will then need a set of two rings, see "related parts" tab.
If you have purchased an engine gasket set for a fuel injection engine (only available for type 1 engines), these gaskets are included. For all other engines (not specifically for injection), you will need to order them separately.
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