Pop Goes the Diesel

"Trucks/Cars are waiting in the Yard; Tackling them with ease'll, 'Show the world what I can do,' Gaily boasts the Diesel. In and out he creeps about, Like a big black weasel. When he pulls the wrong trucks/cars out – Pop goes the Diesel!"

- Troublesome Trucks

Pop Goes the Diesel is the twelfth episode of the second season.

Plot
Duck the Great Western engine works very hard on the Island of Sodor and everything goes smoothly when he is around. He can keep the coaches quiet, the trucks behaving, and the passengers happy. He is also very proud of his Great Western heritage and talks endlessly about it, which irritates the larger engines who quickly grow tired of hearing about "the Great Western way."

One day, a visitor arrives in the shed. The Fat Controller introduces the new engine as Diesel, stating that he is going to be given a trial and charges Duck with showing him around and teaching him what to do. Diesel introduces himself before heaping compliments on Gordon, James, and Henry, which quickly win them around to the newcomer. Duck, however, takes a dislike to Diesel's oily nature and shows him to the yard.

There it becomes apparent that Duck's dislike of Diesel is mutual as Duck orders Diesel to refer to the Fat Controller as "Sir Topham Hatt," before Diesel smugly tells Duck that he does not have to be taught what to do. As a diesel, he already knows everything and that diesels will always improve a yard, calling diesels revolutionary. Duck is not very happy about this and orders Diesel to arrange the trucks while he leaves to take Gordon's coaches to the station.

Diesel, eager for the chance to show off, quickly gets to work. However, he attempts to move the wrong trucks; some really old ones which have stiff joints and brakes. When Diesel cannot move them, he tries getting very forceful with them. Duck arrives, and realises what is happening, but decides to let events play out, and watches with interest. Diesel gets so frustrated with the trucks that he accidentally overturns some when their brakes snap. Diesel still cannot move the remaining trucks and is forced to give up.

As Duck finally comes forward carrying some other trucks, Diesel asks Duck why he did not tell him about the others. Duck simply reminds Diesel that he is supposed to revolutionise the yard. Duck leaves happily, while Diesel fumes.

Diesel is later forced to help clean up the mess, a duty that he hates especially as the trucks have started teasing and singing at him. When the clean-up is over, Diesel, now unhappy with the trucks and with Duck, storms off back to the shed.

Characters

 * Henry
 * Gordon
 * James
 * Duck
 * Diesel
 * Sir Topham Hatt
 * Percy
 * British Railways Diesels (mentioned)
 * The Mainland Diesels (mentioned)

Locations

 * Tidmouth Sheds
 * Knapford Yards
 * Sodor Shipping Company
 * Brendam Warehouse

Trivia

 * This episode is based on the story of the same name from The Railway Series book, Duck and the Diesel Engine.
 * The title, as well as the song featured, is a pun on the nursery rhyme, Pop Goes the Weasel.
 * Despite being Diesel's introduction episode, he previously had a cameo in Percy Takes the Plunge.
 * In the restored version, during both close-ups of Diesel, his eyes move differently compared to the original version of the episode.
 * This is only the first time Diesel tried to pull a line of cars with the brakes on. He would eventually do it again in the sixth season episode, The World's Strongest Engine.
 * In some UK versions, the narrator is not singing with the trucks during their song.
 * In the Polish version, Diesel does not growl while Duck is leaving. Similarly, it sounds like Diesel laughs while Duck is leaving in the Japanese version.
 * In the Korean and Hungarian versions, the song sung by the Troublesome Trucks is still in English, though the Korean version of the song has subtitles.
 * In Ringo Starr's US narration, he did not re-sing Pop Goes the Diesel. Instead, the instances of the word "trucks" were replaced with "cars."
 * When Diesel "gave a great heave," the footage is reversed. The derailed truck behind him can be seen propping itself back up on the rails as Diesel pulls forward.

Goofs

 * When Duck is on the turntable in the beginning, the turntable bounces back and forth a little when it stops.
 * In the scene where Duck is exactly side-on, a small space between the face and the model is visible.
 * Henry's tender is missing in the first shot featuring him.
 * When Duck passes James, Gordon, and Henry, there are only two tracks to the right of the water tower and it is not in line with the Sodor Shipping Company building. When Diesel and Duck arrive later on, there are three tracks to the right of the water tower and it is in line with the building.
 * Gordon and Henry's faces are crooked when Duck and Diesel leave.
 * When Duck and Diesel frown at each other Duck is missing his eyebrows. Duck is also missing eyebrows when Diesel first backs into the shed.
 * Duck is not in the siding when Diesel tries to pull the trucks.
 * When Diesel loses patience with the trucks and pulls them even harder, The first few trucks are already derailed, but when Diesel is still trying to pull them in the next scene, they are not derailed.
 * Steam can be seen around Diesel when he is trying to move the trucks.
 * When the narrator says "Diesel lost patience," one of the trucks has a clump of hair inside it.
 * When Diesel tries to push the trucks back, he backs down onto the breakdown train, not the trucks. In the same scene, one of the buffer stops on the left is leaning over.
 * In one scene, there is not a truck in the siding that Duck is in before he goes to collect the other trucks. One appears in the siding during the trucks' song, then after it finishes there is not.
 * In the scene of Duck seeing Diesel after he collects his trucks, Diesel backs down to the trucks he was struggling with - straight into them - then he comes forward a little so as to be directly in line with Duck. Last of all, when Duck leaves, he goes backwards suddenly before heading off.
 * When Duck runs around to collects his trucks, his eyes jitter a little before he stops to talk to Diesel.
 * After Duck leaves to get Gordon's coaches, there is still steam venting from the track.
 * When the narrator says "Diesel had to help the workmen clear the mess," the breakdown train is missing one of its buffers.
 * Throughout the Knapford Yards and Brendam Warehouse scene sequence, Diesel is missing his eyebrows.
 * In a rare picture, Diesel's siderods are crooked.
 * Henry's whistle sound is lower pitched at one point during the scene at Tidmouth Sheds.
 * When Diesel first tries to move the trucks, a china clay truck derails.
 * The narrator says that Diesel was delighted to show off, but he is still frowning.
 * While Diesel tries to move the trucks, the truck right behind him is a china clay truck but when he pulls the truck of the track, it appears to be a coal truck.

Quotes

 * Trucks: (groan while Diesel tries to pull them) We can't! We won't!

Merchandise

 * Buzz Books - Pop Goes the Diesel
 * Ladybird Books - Pop Goes the Diesel/Dirty Work/A Close Shave

Home Media Releases
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UK

 * Percy and Harold and Other Stories
 * The Biggest Ever Christmas Collection
 * The Complete Series 2
 * The Very Best of Thomas and Friends
 * Percy Takes the Plunge (UK DVD)

DVD Boxsets

 * Classic Collection
 * The Fogman and The Very Best of Thomas and Friends Double Pack

US

 * Better Late Than Never and Other Stories (Ringo Starr's narration)
 * James Learns a Lesson and Other Stories (George Carlin version only in 1995 release)
 * Thomas Comes to Breakfast and Other Thomas Adventures
 * Thomas' Useful Stories
 * Thomas & Friends Classic Volume 2

DVD Boxsets

 * Adventure On the Tracks
 * Totally Thomas Volume 9

AUS

 * Percy and Harold and Other Stories
 * The Biggest Ever Christmas Collection
 * The Very Best of Thomas and Friends
 * The Complete Series 2
 * My First Thomas with Diesel

DVD Boxsets

 * 60th Anniversary - Limited Edition Boxset
 * Essential Collection (Five Disc Collection)
 * Complete Series 1-10 (Boxset)
 * My First Thomas
 * Classic Collection
 * Series One and Series Two Double Pack

NZ

 * Percy and Harold and Other Stories
 * The Biggest Ever Christmas Collection
 * Bumper Video Collection Volume 3
 * Thomas Train Set Compilation Video Volume 6

JPN

 * Thomas the Tank Engine Volume 9
 * The Complete Works of Thomas the Tank Engine 1 Vol.2
 * The Complete DVD Box 1
 * I Will Not Loose to the Diesel

PHL

 * Percy Takes the Plunge (Philippine DVD)

GER

 * Thomas and His Friends Vol. 4
 * The Runaway and 4 Other Adventures
 * Rail Free for Steam and Diesel!

HRV

 * Duck Takes Over

UKR

 * A Train Thomas and Friends

NL

 * Percy and Harold (Dutch DVD)
 * The Greatest Stories: The Adventures of Edward, Toby and the Diesels

NOR/FIN/ISL

 * Thomas the Tank Engine 4 (Norwegian VHS/DVD)

ITA

 * The Locomotive and the Helicopter

DNK

 * The Runaway Train and Other Stories

BRA

 * The Earliest Adventures of Thomas

Latin America

 * The Visit of Thomas

DVD Boxsets

 * The Adventures of Thomas

IND

 * Pop Goes the Diesel and Other Stories

MYS

 * Percy Takes the Plunge and Other Thomas Adventures

ROM

 * Thomas and the Great Runaway (DVD)

DVD Packs

 * Triple Pack 1

SER

 * Thomas the Tank Engine 3

CHN

 * Thomas and Friends Season 1-4 (DVD)

THA
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 * Thomas and Friends - Volume 6 (Thai DVD)
 * Thomas and Friends Volume 4 (Thai DVD)

Schöner Mist, Herr Diesel! Diesel da la Nota הנה קופץ הדיזל ディーゼルがやってきた Samochwała Diesel