On Water Boxer (WBX) engines, this water flange is located on the right cylinder head at the rear and on the Diesel engines also on the right side cylinder head at the rear.
Corrosion makes it necessary to replace the flanges, although you can limit this phenomenon by using the appropriate coolant, which is indicated on the "Options" tab.
When you buy this new flange, you don't have to worry about rust, the model for the Water Boxer (WBX) engine is made of stainless steel (also the mounting material) and the one for the Diesel engine is identical to the original, made of aluminium.
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