RealOEM.com BMW Parts website. This site can be used to look up BMW part numbers and approximate part prices. The Parts are grouped into diagrams and diagrams are grouped into categories and subcategories
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Put last 7 letters and numbers of your Vin in and the look at engine parts section for gasket part number either buy from BMW, Autodoc or eBay on the latter they usually around £4. Fitting, air box out, belts off and alternator out then undo the oil filter housing 4 bolts to remove, clean mating surfaces reinstall with new gasket, no sealant required. Like all gaskets the go hard and brittle with continued heat cycles and age hence leaks. Be prepared for same with cam cover and centre spark plug gaskets. For these I used an Elring gasket kit that includes 15 round cover bolts seals, they need replacing with the gaskets to achieve correct tightening of the cover. Old ones won't compress sufficiently as they go hard as well.