He regained his splashers, with the third pair being cut off from where his tapered firebox was.
His stepladder became solid, instead of hollow.
He gained two extra brake pipes, all four now facing downwards.
In Duck Takes Charge, and in some scenes of Dirty Work and A Close Shave, his whistle is Duck's six half steps higher in pitch.
Series 3:[]
His eyebrows became smaller.
His front right and back left brake pipes were facing upward again.
In Tender Engines, his front left and back right brake pipes were removed.
Series 5 (only):[]
There was extra yellow lining added to his quarter windows, this was to match the whole windows and keep continuity since the large scale model featured lining on both windows.
Thomas and the Magic Railroad:[]
His paint was given a matte finish.
The gap between his second and third boiler bands becomes larger due to misplaced lining.
His tender lining had its spacing from the edge made even all around, thus making it no longer match the lining on his cab which was higher at the bottom due to the thick red stripe running along his side.
His two safety valves were reduced to a single safety valve due to one of Gordon's going missing and Henry's second being used to replace it.
His eyebrows became more slanted.
His window frame lining became thinner.
Series 6:[]
His eyebrows became longer.
His front left bogie wheel became a 12 spoke type due to being mixed-up with Gordon's front left bogie wheel which was on a 12 spoke set. Gordon has Henry's 10 spoke on his front left with a 12 spoke on his front right.
Series 10:[]
His front cab windows became slightly wider and shorter. (brass model)
The riveting on his front bufferbeam disappeared. (brass model)
His perspex model has visible damage to his front left side.
Series 11:[]
The damage seen in the previous series was repaired.
Series 12:[]
His eyebrows became thicker.
His crow's feet disappeared.
The uneven spacing of his boiler lining went back to how it was originally.
Henry's tender does not have a coal load in the episodes Thomas' Train and Oliver's Find. The first being a photo taken during a scene setup (note James also has no coal load) while the other is a deleted scene.
Hero of the Rails:[]
He lost his front brake-pipe outlet.
His crow's feet reappeared.
The red lining on his wheel arches became thinner and he got lining on the back of his cut-off wheel arch.