They were delivered in Loco Green (the darker shade commonly called Brunswick). The standard practice at the time was that suburban stock was not lined. However after protest from the WR General Manager over their bland appearance, sets began to be delivered from the manufacturers lined. The correspondence shown from Pressed Steel (dated 5th April 1960) suggests this happened from the 20th set onwards. Yet pictured is lined W51343 when just six months old when seen in Reading depot, 24th October 1960 (Adrian Vaughan). As W51343 was in the 12th set, and the 4th set that would be delivered in April 1960, (i.e. four sets after the leter was writted) it seems possible that 19 vehicles not sets had been completed by then. It seems unlikely that W51343 would have been lined after delivery as unlined sets were still to be seen in 1962.
All had white roof domes and whiskers, and at least the first set had some of the underframe equipment picked out in silver (see the works images). Writing could often be seen on the buffer beams to the left of the coupling hook, this referred to them being fitted with with ATC gear.
All were eventually lined as they passed through shops, with yellow panels replacing whiskers from about '64.
Sanding down 51382 for repainting at the Midland Railway Centre in 2003, the original lining was exposed, and this measured: top - 1" wide, 5" from lower gutter edge; bottom - cream 1 1/2" with 1/16th black edges, 6 1/4" from lower window rubber.
In '67 at least one set received the short-lived all-blue livery variation with small yellow panel, white cab dome and red buffer beam, umber underframe, small numbering and the new BR logo on the cab doors. For an example in this style see the September 1967 issue of Railway World, page 413, the 1968 DMU ABC p18 showing W51379 (set 402), or 1970 DMU ABC p20. I haven't (yet) seen an images of the class in the other early variation of all-blue with full yellow ends and yellow cab doors.
This image shows the standard blue livery with full yellow ends. The cab dome became the same colour as the roof, and black buffer beams/underframe, and standard numbering etc. The image shows set 421 running as a 4-car set with Class 101 trailer W59528 at Wylye on 12th April 1971 (David Mant). The next subtle change was the loss of the 4-character indicator, being replaced with two white dots.
Refurbishment saw the white / blue stripe refurbished livery appearing from 1976, as featured on 51397 / 59507 / 51355 at Windsor Central on the 15th June 1980 (Robert Frise).
From about 1980 they started appearing in blue/grey livery, and the sample photo shows set T302 (cars 51360 / 59512 / 51402) entering Birmingham Moore St on 23/10/87 (Mac Winfield). London sets in the Network South East era could be seen carrying NSE stickers while in BG livery, these would be under the center cab window or on the side of the center car.
When NSE livery appeared, there were two variations in the lining. Where the lining swept down at the cab sides, initially it was an angled change to horizontal, later this was altered to a curve.
The first close up shows the angled type (51369 & 51366 face-to-face at Reading, 29/6/87, Malcolm Clements), the second shows the curved one. The yellow no longer reached the edge of the cab door as it did in BG livery. In the second images also note the lack of BR logo, and the gap in the gutter that allowed the water to drain (away from doors/windows).
A one-off livery appeared for the GWR 150th anniversary celebrations when 51368 / 59520 / 51410 were painted into Chocolate & Cream. They worked in these colours as T305, B430 and 117 305. It's seen in the image as T305, working "The Birchfield Rambler" at Quainton Road on the 2nd May 1988 Robert Frise.
The final livery for passenger vehicles was the facelifted sets for Birmingham Cross-City services appearing in Regional Railways colours. The sets that were then transferred to Scotland received ScotRail markings in place of the RR ones.
It shows set 117 314 at the Doncaster Works open day, 12/7/92. Kevin Dowd.