David Benton wrote:I seem to remember the main problem was with the Voith gearboxes.
The Voith gearboxes were the replacement to the original, and it happened about 5 years after introduction.
Though it should be noted that there are 2 different versions of the Pacer - the Class 142 (Leyland based) and the Class 143/144 (Walter Alexander based) plus the Class 140/141 prototypes/test vehicles.
In addition to the transmission and engine issues, the 142s also had reliability issue with their doors, which were replaced with the type of doors from the 143 design.
Despite those 2 issues it really was the 4 wheel chassis that booted them off the branchlines, particularly in Cornwall. The tight curves resulted in excessive squeal and heavy flange wear. Compounding the issue was their lightness which meant the often struggled on steep sections of line (I was on a 142 on a rainy day that barely made it from Torquay to Torre as the wheels kept slipping, a 2 minute journey to just over 10 minutes).
The result was that 142s were quickly booted out of the Western Region, replaced with loco hauled / old DMUs / and for a short while the Class 155 units until the decision was made to split them up and create the 153s.
David Benton wrote:
I also rode many "bubble railcars in the late eighties in England. These were pretty much what the pacers and sprinters were replacing. While the large windows were attractive, I would say the ride and noise level was inferior to the Pacer, and the Sprinters were a huge improvement on them .
I didn't get any bubble cars but did get the sisters (class 101/108/118) which had to return after the failure of the Skippers. They were definitely showing their age at that point but ride quality was no contest. There is a reason the Pacers are nicknamed Nodding Donkeys, and it isn't a good reason. The units would bounce just accelerating away from a station stop and were quite rough going through switches.