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Injector Return Line Banjo Seal for Case 580K, 580SL, 590SL, 1845C, 650K – J903380

SKU:
J903380
FitsModel:
480E, 480F, 580SE, 580K, 580SK, 580L, 580SL, 590 Turbo, 590SL, 580M, 580SM, 590SM (Series I), 480LL, 480F LL, 570LXT, 570MXT, 584E-586E, 585G-588G, 686G, 450C, 455C, 550, 550E-H, 650, 650E-K, 750H, 750K, 1840, 1845C, 40XT-95XT, W11B, W14B, 660, 760
ListDescription:
Injector Return Line Banjo Seal
Injector return line banjo seal J903380 for Cummins 6BT engine
Part # J903380

Fits Models At A Glance:

  • Case Loader Backhoes: 480E, 480F, 580 Super E, 580K, 580 Super K, 580L, 580 Super L, 590 Turbo, 590 Super L; 580M, 580 Super M, 590 Super M — Series I
  • Case Loader Landscapers: 480 LL, 480F LL, 570LXT, 570MXT
  • Case Rough Terrain Forklifts: 584E, 585E, 586E, 585G, 586G, 588G
  • Case Telehandlers: 686G
  • Case Crawler Dozers: 450C, 455C, 550, 550E, 550G, 550H, 650, 650E, 650G, 650H, 650K, 750H, 750K
  • Case Skid Steers: 1840, 1845C, 40XT, 60XT, 70XT, 75XT, 85XT, 90XT, 95XT
  • Case Wheel Loaders: W11B, W14B
  • Case Trenchers: 660, 760

Key Notes:

  • Part Numbers: J903380
  • Interchange Numbers: 3903380, 4942278 (Cummins — 3903380 is superseded to 4942278)
  • Type: One-piece folded copper banjo connector seal — two sealing rings joined by a strap, folded so one ring seats on each side of the banjo fitting
  • Size:
    • Inner Diameter (ID): 0.24 Inches / 6.2 mm
    • Outer Diameter (OD): 0.39 Inches / 9.9 mm
    • Height (H), Folded: 0.66 Inches / 16.75 mm
  • Location: At the banjo bolt where the injector fuel return (leak-off) line connects
  • Engine Compatibility: Cummins B-Series 4B, 4BT, 4BTA (3.9L) and 6B, 6BT, 6BTA (5.9L) — Case 4-390, 4T-390, 6-590 and 6T-590 engines
  • Quantity Required: Sold individually — one per return line banjo connection
  • Fitment Note: Some models listed were built with more than one engine. Confirm your machine has a Cummins B-Series engine before ordering.
  • Application: Seals both faces of the return line banjo fitting under the banjo bolt, keeping fuel in and air out of the fuel system.
  • Condition: Aftermarket replacement part

Common Use Case or Symptoms: Use any time the fuel return line or banjo bolt is removed, or when fuel seeps or air is drawn in at the return line banjo — a reused or flattened copper seal won't reseal and can cause hard starting and loss of prime.

Why Choose Broken Tractor:

  • ✅ One-Piece Folded Seal Covers Both Sides of the Banjo – no separate washers to keep track of
  • ✅ Fresh Copper Seals Every Time the Line Comes Off – stops leaks and air in the fuel system
  • ✅ Fast Shipping from a U.S.-Based Team – ready to ship from our U.S. warehouses
$2.00

Shipping calculated at checkout. If any item in your order is temporarily unavailable, we'll contact you to arrange a back-order or refund — whichever you prefer.

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Product: Category: Brand: Head Title: Injector Return Line Banjo Seal | Broken Tractor | J903380