This 2011 328i was brought to us for some repairs we quoted earlier this year. We noticed oil leaking from the oil filter housing, and also the serpentine belt working its way off the tensioner pulley.
We replaced the oil filter housing gasket, along with the serpentine belt tensioner and belt.
The oil filter housing gasket, much like the valve cover gasket, is an extremely common leak. We see this leak predominantly with 6 and 4 cylinder BMW’s.
A failing serpentine belt tensioner is also a common occurrence. We see this mostly on N52 engines, such as in this 328i, but also N54/N55 engines as well.
Advice From The Experts
Oil Filter Housing Gasket Leak
If left un-repaired, the oil filter housing gasket leak will cover the front of the engine in oil. This includes potentially saturating the upper radiator hose, leaving the rubber mushy and more prone to failure. Various connector leads on the engine harness can become soaked in oil. In extreme cases, the gasket can completely fail and cause a mixture of oil and coolant inside the engine.
Belt Tensioner Repair
The belt tensioner repair is also one that shouldn’t be postponed. The mechanical style tensioner will become cocked and throw the serpentine belt off the pulley. When this happens, there’s a good chance the crankshaft balancer will draw the belt in behind itself, damage the front crank seal, and put shreds of belt material inside your engine. Many times when this happens, the oil pan must be removed to remove the pieces of serpentine belt from the oil sump pick up and even timing chain.