Oiling System for BMW 3 Series E46 (1999-2005)

If your M50, M52, or M54 engine takes a few seconds to build oil pressure after sitting, there's a good chance that your factory oil filter housing drain back valve has failed. Over time, the factory plastic check valve degrades, allowing oil to drain completely out of the housing and back into the oil pan while sitting. Every cold start essentially becomes a dry start, resulting in a loud ticking noise and causing unnecessary wear on your engine's internals.

Unfortunately, BMW does not offer this check valve as a standalone part, forcing you to purchase a costly, complete oil filter housing assembly just to fix one failed plastic component. Thankfully, our team of BMW enthusiasts took note of this common failure mode and designed a permanent, cost-effective fix.

Our Billet Oil Filter Housing Drain-Back Valve is designed as a direct-fit upgrade for your factory oil filter housing. CNC-machined from high-strength billet aluminum, this upgraded valve restores positive sealing to keep the oil filter housing fully primed. Maintaining this hydraulic prime ensures rapid oil pressure stabilization upon startup, directly mitigating dry-start bearing wear and top-end lifter starvation without requiring the purchase of a complete OEM housing assembly.

Modern day emissions regulations require the use of a closed crankcase ventilation (PCV) system to recirculate combustion blow-by gases from the crankcase back in to the intake to be burned.  Unfortunately, these blow by gases contain water vapor (which is a byproduct of combustion) and pick up oil mist from and the windage cloud and cam lubrication system as they travel through the crank case.  Due to less than 100% effective air/oil separation in the stock PCV system, some oil mist and water vapor gets carried back to the intake tract and over time cause oil deposits in the intake manifold, intake ports, and on the back of intake valves.  All will eventually lead to poor performance and reduced fuel economy, and the presence of this oil mist in the intake charge may even increase the risk of engine-damaging detonation. 

With forced induction, track use, and/or extended high RPM usage, these symptoms increase as the factory PCV system is overwhelmed, and a catch can becomes a must for your E46 M3. This kit is a direct fit making this an easy reversal if desired as well as maintaining a clean appearance by utilizing the open "smuggler's compartment" on the passenger side of the engine bay.

*Click here for catch can instructions*

Features:

• 6061-T6 billet machined body, anodized black for lasting protection and appearance
• Strategically positioned 4 chamber baffle system maximizes oil / air separation 
• Knurled and black anodized oil dipstick makes inspecting oil volume of reservoir clean and simple
• Sealed with a pre-installed viton o-Ring
• Includes 2.5mm allen key to remove baffle plates for cleaning
• Engineered to create multiple changes in the direction of airflow within the separator to cause oil droplets to fall out of suspension before exiting the catch can
• Closed / recirculated design reduces oil ingestion and promotes cleaner emissions and odor-less operation
• Valved drainage system - no removal of can necessary to empty

Stainless steel filtration is not a new technology but is quickly gaining popularity in the automotive segment. With the ability to filter down as small as a paper filter element with the ability to be washed and reused!

The K&P Engineering filter element is made from medical grade, type 304 stainless steel micronic filter cloth to provide unmatched protection against oil contamination and resultant engine damage. A one inch square of this material flows an incredible 1.9 gallons of oil per minute at only 1 PSI pump pressure. The adhesive used in the filter assembly process is good to 600 degrees Fahrenheit, far above normal engine operating temperatures. A super strength nickel-plated neodymium rare earth magnet is installed in the top of the element for magnetic pre-filtering of the oil. The sophisticated bypass is engineered for proper differential pressures and consistent operation, delivering a greater percentage of filtered oil while being very easy to clean. The twist lock design assures positive filter element placement and allows for easy disassembly, inspection, and cleaning. The quad-ring gasket doubles the seal between the filter and the engine. Finally, the filter housing is carved out of solid 6061T6 billet aluminum, which not only looks trick but aids in dissipating heat.

K&P Engineering manufactures stainless steel filters for a vast array of engines around the world. Staying at the forefront of design and testing allows this company to offer a top-tier product for your European vehicle.

Features:

• Consistent filtering across entire filter surface
• Superior ASTMF316 filtration performance
• 7 times the flow of comparable paper oil filters
• Magnetic Prefiltering
• Progressive rate bypass combined with high flow characteristics of the filter media avoids unfiltered oil bypassing the filter during cold startup and high rpm
• No more cutting apart messy paper filters for trapped debris inspection
• Proven in Motorsports, Military and Aerospace applications for years. Technology is FAA approved for use in aircraft. 

At regular oil changes, clean to K&P's specifications for continued used - a true lifetime filter.

This product fits the following BMWs:
1995 - 1999 E36 M3
2001 - 2006 E46 M3
1998 - 2002 E36/8 Z3 M Coupe
1998 - 2002 E36/7 Z3 M Roadster
2006 - 2008 E86 Z4 M Coupe
2006 - 2008 E85 Z4 M Roadster

Stainless steel filtration is not a new technology but is quickly gaining popularity in the automotive segment. With the ability to filter down as small as a paper filter element with the ability to be washed and reused!

The K&P Engineering filter element is made from medical grade, type 304 stainless steel micronic filter cloth to provide unmatched protection against oil contamination and resultant engine damage. A one inch square of this material flows an incredible 1.9 gallons of oil per minute at only 1 PSI pump pressure. The adhesive used in the filter assembly process is good to 600 degrees Fahrenheit, far above normal engine operating temperatures. A super strength nickel-plated neodymium rare earth magnet is installed in the top of the element for magnetic pre-filtering of the oil. The sophisticated bypass is engineered for proper differential pressures and consistent operation, delivering a greater percentage of filtered oil while being very easy to clean. The twist lock design assures positive filter element placement and allows for easy disassembly, inspection, and cleaning. The quad-ring gasket doubles the seal between the filter and the engine. Finally, the filter housing is carved out of solid 6061T6 billet aluminum, which not only looks trick but aids in dissipating heat.

K&P Engineering manufactures stainless steel filters for a vast array of engines around the world. Staying at the forefront of design and testing allows this company to offer a top-tier product for your European vehicle.

Features:

• Consistent filtering across entire filter surface
• Superior ASTMF316 filtration performance
• Magnetic Prefiltering
• Progressive rate bypass combined with high flow characteristics of the filter media avoids unfiltered oil bypassing the filter during cold startup and high rpm
• Easy inspection of engine contamination
• Proven in Motorsports, Military and Aerospace applications for years. Technology is FAA approved for use in aircraft. 

At regular oil changes, clean to K&P's specifications for continued used - a true lifetime filter.

This part fits the following BMWs:
1991 - 1999 E36 Coupe 323i 325is 328i
1993 - 1999 E36 Convertible 323i 325i 328i
1990 - 1999 E36 Sedan 325i 328i 
1989 - 1995 E34 525i, 530i, 
1998 - 2004 E39 Touring 525i 528i 
1996 - 2004 E39 Sedan 525i 528i 530i 
1999 - 2001 E46 Convertible 323ci 325ci 330ci
2002-2006 E46 Convertible 325ci 330ci
1998 - 2001 E46 323ci 325ci 330ci M3
2002 - 2006 E46 325ci 330ci
1998 - 2001 E46 Touring 323i 325i
2002 - 2006 E46 Touring 325i 325xi
1998 - 2001 E46 Sedan 323i 325i 328i 330i
2002 - 2006 E46 Sedan 325i 325xi 330i 330xi
2000 - 2006 E53 X5 SUV X5 X5 3.0i