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LEGO Missing Piece Checker

Rule out the usual hiding places first. If the piece really is gone, check the set piece by piece and leave with the element ID LEGO asks for, or a link to buy the part.

Crocodile Locomotive

Checking

4551 Crocodile Locomotive

310 pieces in 91 part and color combinations, plus 1 minifigure.

The official piece count includes the 4 parts inside the set's minifigures, which this inventory lists separately. Spare parts are counted in neither figure.

Before you call it missing

Builders who report a missing piece often find it in one of these places. Tick each one off as you look.

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Piece checklist

Red 122 pieces

  • Brick 1 x 1 Red Part 3005 Element 300521 ×10
  • Brick 1 x 2 Red Part 3004 Element 4613961 or 300421 ×12
  • Brick 1 x 4 Red Part 3010 Element 301021 ×6
  • Brick 1 x 6 Red Part 3009 Element 300921 ×2
  • Brick 2 x 2 Red Part 3003 Element 4103590 or 300371 ×2
  • Brick 2 x 4 Red Part 3001 Element 300121 ×2
  • Brick Curved 2 x 4 x 2 Double [Plain] Red Part 4744 Element 474421 ×2
  • Brick Sloped Inverted 45° 2 x 1 Red Part 3665 Element 366521 ×2
  • Brick Special 1 x 1 with Headlight Red Part 4070 Element 407021 ×4
  • Brick Special 1 x 2 with Grille Red Part 2877 Element 6219677 or 287721 ×24
  • Plate 1 x 10 Red Part 4477 Element 447721 ×4
  • Plate 1 x 2 Red Part 3023 Element 302321 ×26
  • Plate 1 x 4 Red Part 3710 Element 371021 ×4
  • Plate 2 x 12 Red Part 2445 Element 4255035 or 4161545 ×1
  • Plate 2 x 4 Red Part 3020 Element 302021 ×3
  • Plate 2 x 6 Red Part 3795 Element 379521 ×1
  • Plate 4 x 12 Red Part 3029 Element 4514717 or 302921 ×1
  • Plate 6 x 8 Red Part 3036 Element 303671 or 303621 ×2
  • Technic Brick 1 x 2 [1 Pin Hole] Red Part 3700 Element 370021 ×2
  • Tile 1 x 4 with Groove Red Part 2431 Element 243121 ×2
  • Tile 1 x 8 with Groove Red Part 4162 Element 416221 ×4
  • Train Door 1 x 4 x 5 Left White Stripe Train Logo Print Red Part 4181pr0008 Element 81697 ×2
  • Train Door 1 x 4 x 5 Right White Stripe Train Logo Print Red Part 4182pr0008 Element 81696 ×2
  • Train Front with 1 x 4 x 3 Cutout Red Part 2924a Element 292480 ×2

Black 118 pieces

  • Bracket 2 x 2 - 2 x 2 Black Part 3956 Element 6254808 or 6019217 ×1
  • Brick 1 x 2 Black Part 3004 Element 300426 ×3
  • Brick 1 x 4 Black Part 3010 Element 301026 ×1
  • Brick 2 x 2 Black Part 3003 Element 4103587 or 300326 ×1
  • Brick 2 x 4 Black Part 3001 Element 300126 ×2
  • Brick Round 1 x 1 with Fins, Open Stud Black Part 4588 Element 6039178 or 4246931 ×1
  • Brick Sloped 33° 3 x 2 Black Part 3298 Element 329826 ×1
  • Brick Sloped 45° 2 x 2 Double Convex Black Part 3045 Element 4189064 or 304526 ×2
  • Brick Sloped 45° 2 x 2 with 3 Gauges and 3 Knobs Print Black Part 3039pr9970 Element 4251812 or 4163777 ×1
  • Brick Sloped 45° 2 x 4 Black Part 3037 Element 303726 ×2
  • Brick Sloped Inverted 33° 3 x 2, No Connections between Studs, Ovoid Bottom Pin Black Part 3747a ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Black Part 3660 Element 366026 ×4
  • Brick Sloped Inverted 45° 4 x 2 Double with 2 x 2 Recessed Black Part 4871 Element 4188534 or 487126 ×1
  • Brick Special 2 x 4 x 2 with Studs on Sides Black Part 2434 Element 4494850 or 4201520 ×2
  • Cone 1 x 1 [No Top Groove] Black Part 4589 Element 4518219 or 458926 ×1
  • Engine - Smooth, Small 1 x 2 Side Plate [With Axle Holders] Black Part 3475b Element 347526 ×2
  • Equipment Control Panel Black Part 2342 Element 4164402 or 234226 ×1
  • Hinge Bar 2.5L with 2 and 3 Fingers on Ends (Pantograph Shoe Holder) Black Part 2923 Element 292326 ×4
  • Magnet Cylindrical Black Part 73092 Element 73092 ×2
  • Minifig Head [Plain] [Blocked Open Stud] Black Part 3626b ×2
  • Motor, Train Base, 9V [Complete Assembly] Black Part 70358 Element 70358 ×1
  • Plate 1 x 2 Black Part 3023 Element 302326 ×7
  • Plate 1 x 4 Black Part 3710 Element 371026 ×5
  • Plate 1 x 6 Black Part 3666 Element 366626 ×1
  • Plate 2 x 10 Black Part 3832 Element 383226 ×1
  • Plate 2 x 2 Black Part 3022 Element 302226 ×5
  • Plate 2 x 2 Corner Black Part 2420 Element 242026 ×4
  • Plate 2 x 3 Black Part 3021 Element 302126 ×10
  • Plate 2 x 4 Black Part 3020 Element 302026 ×4
  • Plate 2 x 8 Black Part 3034 Element 303426 ×8
  • Plate 4 x 6 Black Part 3032 Element 303226 ×1
  • Plate Round 1 x 1 with Solid Stud Black Part 6141 Element 614126 ×4
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Black Part 4081b Element 6281993 or 4632571 ×4
  • Tail 4 x 2 x 2, Rocket Black Part 4746 Element 4164411 or 474626 ×1
  • Technic Plate 2 x 4 [3 Holes] Black Part 3709 Element 370926 ×2
  • Technic Plate 2 x 8 [7 Holes] Black Part 3738 Element 373826 ×4
  • Tile 1 x 2 with Groove Black Part 3069b Element 306926 ×4
  • Tile Special 1 x 2 Grille with Bottom Groove Black Part 2412b Element 241226 1 spare in the box ×1
  • Tile Special 2 x 2 with Top Pin Black Part 2460 Element 4258354 or 246026 ×2
  • Tile Special 6 x 4 with Beveled Edges and 5mm Pin (Train Bogie Plate) Black Part 4025 Element 6096842 or 6051914 ×1
  • Train Buffer Beam Black Part 4022 Element 4109853 or 402276 ×2
  • Train Coupling New Black Part 2920 Element 4299239 or 292076 ×2
  • Train Motor Decorative Side 10 x 2 x 2 with Closed Hub Points (for 9V Train Motor) Black Part 2871a ×2
  • Train Pantograph Shoe with Hinge Black Part 2881 ×2
  • Wheel Holder, Train with Wheels [Complete Assembly] Black Part 2878c01 Element 4207401 or 74784 ×4

Light Gray 41 pieces

  • Brick 2 x 4 Light Gray Part 3001 Element 4116259 or 300102 ×1
  • Brick Sloped 45° 2 x 6 x 2/3 Light Gray Part 2875 Element 287502 ×4
  • Brick Special 1 x 2 with Grille Light Gray Part 2877 Element 287702 ×8
  • Brick Wedged, Sloped 45° 6 x 6 Double / 33° [Train Roof End] Light Gray Part 2876 Element 4140488 or 287602 ×2
  • Hinge Tile 1 x 2 1/2 with 2 Fingers on Top Light Gray Part 4531 Element 4256463 or 4163772 ×2
  • Lever Small Base with Black Lever Light Gray Part 298c02 Element 73588 1 spare in the box ×2
  • Plate 1 x 2 Light Gray Part 3023 Element 302302 ×6
  • Plate 2 x 3 Light Gray Part 3021 Element 302102 ×4
  • Plate 4 x 4 Light Gray Part 3031 Element 4243813 or 303102 ×2
  • Plate 4 x 6 Light Gray Part 3032 Element 303202 ×2
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Light Gray Part 3794a Element 379402 ×6
  • Technic Pin 1/2 without Friction Ridges Light Gray Part 4274 Element 427402 1 spare in the box ×2

White 16 pieces

  • Brick 1 x 6 White Part 3009 Element 6552097 or 6548259 ×2
  • Brick Special 1 x 2 with Grille White Part 2877 Element 6552093 or 287701 ×4
  • Plate 1 x 4 White Part 3710 Element 6552108 or 6548266 ×2
  • Plate 1 x 8 White Part 3460 Element 6550141 or 346001 ×4
  • Tile 1 x 2 with Space Computer Print White Part 3069bpr0039 Element 80972 ×2
  • Tile 1 x 2 with Telemetry Panel Print White Part 3069bpr0043 Element 81575 ×2

Trans-Clear 10 pieces

  • Glass for Train Door Lip On Top and Bottom Trans-Clear Part 4183 Element 418340 ×4
  • Plate Round 1 x 1 with Solid Stud Trans-Clear Part 6141 Element 6514052 or 6240030 ×6

Yellow 2 pieces

  • Seat / Chair 2 x 2 Yellow Part 4079 ×2

[No Color/Any Color] 1 piece

  • Sticker Sheet for Sets 4536-1, 4543-1, 4546-1, 4551-1 [No Color/Any Color] Part 164585 Element 164585 ×1

Minifigures 1 figure

  • Conductor - Blue Jacket, Black Legs, Red Hat (3626a Head) Minifigure, checked as a whole figure ×1

Tick each piece as you find it, or mark it missing.

When a piece really is missing

Ask LEGO

LEGO takes requests for pieces missing from a new set through its customer service site. The form asks for the set number and each piece's element ID, the number printed beside the piece in the parts list at the back of the instructions. This checker lists both.

Request a replacement from LEGO

Buy the piece

Mark a piece missing and your list links it to an eBay search for that part, which also covers pieces from older or second-hand sets.

Keep a record

Copy or download your missing list (the CSV opens in any spreadsheet), or print the whole checklist and tick pieces off on paper. Your marks stay in this browser, so you can check a big set over several sittings.

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