The line was electrified and these sets were due to be replaced by Class 317 electric units in May 1982. At the time BR was ridding itself of as many asbestos units as possible. The 127s were asbestos free, but the availability of spare parts for the Rolls-Royce engines was a problem and so the power cars were scheduled for withdrawal at this time.
However the introduction of single man operation on these units caused union opposition, and so the Class 127s had to struggle on for longer, while the new electrics sets sat unused. Keeping them going was a considerable task, as the planned rundown of the class had to be somewhat stretched. This caused an acute shortage of spares, which got so bad by December 1982 that they had to take an engine from 51156, a Class 125 DMBS which had been in store at York as a potential departmental car. For the last few winters all serviceable units had to be left with their engines running for fear of them not starting again, despite complaints from residents beside the stabling point.
A farewell tour ran on the 12/3/83 from St Pancras taking in Bedford, Bletchley, Quainton Road, Marylebone, Neasdon and Acton Wells, before traversing the GWR main line to Slough. Damage to an air receiver en-route was repaired by the Quainton Railway Centre enabling the tour to continue.
Problems continued with the 317s, and the 127s (many if not all as three cars) were temporarily re-introduced on to selected peak hour workings between St.Pancras and Bedford (generally with first stop St. Albans) during the summer of 1983, and contributor Jonathan Rix noted there was a lot of furore in the local press about this.
On the 28th May 1983 two sets worked a Loughborough to St Albans charter.
Ten three-car sets were retained to replace Class 116s on the Gospel Oak to Barking line from 20/6/83, the 116s moving to Birmingham. This was until sometime early in 1984, by which time many were been reduced to 2-car formations. Their replacements were cascaded Class 104's.
The last booked St Pancras - Bedford working was the 21:53 from St Pancras on the 10/7/83 formed of 51646/59606/59643/51592. However, the next day saw three sets used on a Bedford - Flitwick shuttle because of engineering work.
The first vehicle to be withdrawn was 51609, less than five years old in April 1964 following a derailment between Hendon Junction and Kettering in Dec 63. It was cut up at Derby Litchurch Lane in 1966. 51594 was withdrawn next in Nov. 1966 after sustaining fire damage at Sandridge. The next month 59635 was withdrawn with accident damage at Cricklewood. 59601 went in June 68 as "life expired", as was 59599 in Dec 72. 51629 was withdrawn in Jan 75 after fire damage while operating a football special.
On the 25th June 76 an 8-car set had problems at Luton, and entered the crossover to gain access to the slow line. It was hit by the 18:18 St Pancras - Bedford unit, which was derailed across the fast line, and was subsequently hit by a St Pancras - Derby express. Fortunately there were no deaths, except 51602, 51632, 59618, 59624 and 59630. These were taken to Litchurch Lane for scrapping, 51607 and 51617 also went along for repair.
51591 was withdrawn in May 1977 but reinstated two months later. On the 8th Nov 1977 the 17:50 Bedford - St Pancras set collided with the rear of a St Albans - St Pancras set. Both DMBS's involved, 51601 and 51641 were beyond repair. 51631 was withdrawn in Sep 79 after accident damage, and cut up at CW in Feb 80.
Power cars 51594 and 51614 were severely damaged by a fire at the Bedford Stabling point on the evening of 1st April 1983. 51614 was cut up on site a week later by BR staff.
Trailers that were spare after their power cars were withdrawn were transferred to Tyseley for use in Class 116 sets. 59617 and 59623 moved in March 1978, followed by 59595 in May 1982 and 59610 in October 1982.
Most of the power cars were withdrawn at the end of 1983, and put into store initially at Cricklewood and then Carlisle. The remaining trailers were refurbished and transferred to Tyseley to replace Class 116 centre cars which contained asbestos, and some lasted for a further ten years, till Oct '93, although the TS's were withdrawn earlier than the TSL's.
Other power cars were stripped of common parts at Leicester TMD before making the short journey to Vic Berrys for cutting up. Once at Vic Berrys the bogies were removed and sent to Doncaster Works, for overhaul and use under Class 114s. While they were directly interchangeable, the Class 127 bogies gave a superior ride.