NISSAN 16781-AD20A Fuel Injection Pump O-Ring

Genuine OEM Nissan fuel injection pump sealing O-ring (part number: 16781-AD20A), designed to ensure a leak-free connection between the fuel delivery system and the high-pressure injection pump. Precise dimensional accuracy and high-grade elastomer material ensure long-lasting sealing performance, even in aggressive fuel environments and under high operating temperatures.

Technical Specifications

• Brand: NISSAN (Genuine OEM part)
• Part Number: 16781-AD20A
• Alternative / OEM Reference Number: 16781AD200
• Part Type: Injection Pump O-Ring
• Material: Fuel- and heat-resistant specialized elastomer
• Function: Prevents fuel leakage and air ingress at the injection pump mating surface

Operational Significance and Failure Symptoms

This O-ring is essential for maintaining correct system pressure in the diesel fuel system. Over time, continuous thermal cycling and the chemical effects of diesel fuel can cause the seal to harden, crack, or deform. Seal failure can lead to fuel leaks, air drawing into the system, resulting in difficult cold or warm starts, and erratic engine running. Whenever the injection pump or high-pressure pump is removed or serviced, replacing this sealing ring is mandatory according to manufacturer specifications.

Compatible Vehicles

• Nissan Almera (N16E) [2000 - 2002] (O RING)
• Nissan Almera Tino (V10M) 2.2 TD [2000 - 2003] (O RING (YD22DDTI))
• Nissan Cabstar (F24M) 2.5 TD [2006 - 2008] (O RING (YD25DDTI))
• Nissan Cabstar Twnmake (F24W) 2.5 TD [2007 - 2008] (O RING (YD25DDTI))
• Nissan Frontier (D40B) [2008 - 2008] (O RING)
• Nissan Frontier (LCD22T) 2.5 TD [2008 - 2009] (O RING (YD25DDTI))
• Nissan Hardbody (D22S) [2006 - 2006] (O RING)
• Nissan King Cab (LCD22) 2.5 TD [2008 - 2008] (O RING (YD25DDTI))
• Nissan Navara Spa Make (D40M) 2.5 TD [2005 - 2010] (O RING (YD25DDTI))
• Nissan Navara Thi Make (D40T) [2008 - 2012] (O RING)
• Nissan Nissan Truck (D22) 3.0 TD [2001 - 2009] (O RING (ZD30DDT))
• Nissan Nissan Truck (D22) 2.5 TD [2001 - 2008] (O RING (YD25DDTI))
• Nissan Nissan Truck Zn (D22F) [2009 - 2009] (O RING)
• Nissan Np300 F/Saf (LCD22S) [2008 - 2010] (O RING)
• Nissan Np300 F/Sbs (D22SS) [2009 - 2011] (O RING)
• Nissan Np300 Pickup (D22X) [2008 - 2009] (O RING)
• Nissan Pathfinder Spn (R51M) 2.5 TD [2005 - 2010] (O RING (YD25DDTI))
• Nissan Patrol (Y61) 3.0 TD [2000 - 2012] (O RING (ZD30DDTI))
• Nissan Primera (P12E) 2.2 TD [2001 - 2004] (O RING (YD22DDT))
• Nissan Pulsar (N16) 2.2 TD [2000 - 2001] (O RING (YD22DDT))
• Nissan Pulsar (N16) 2.2 D [1999 - 2003] (O RING (YD22DD))
• Nissan Terrano2 (R20) [2002 - 2004] (O RING)
• Nissan Urvan (E25) 3.0 TD [2003 - 2009] (O RING (ZD30DDTI))
• Nissan Urvan (E25) 3.0 D [2001 - 2009] (O RING (ZD30DD))
• Nissan X-Trail (T30) 2.2 TD [2001 - 2006] (O RING (YD22ETI))