During the delivery of the Mark Four coaches and DVT's to Bounds Green in connection with the introduction of IC225 on ECML, the commissioning teams of Metro Cammell were hard at work sorting out the teething problems.

The BR commissioning team was there to ensure that they stuck to their task.

The first trip for a rake of newly-delivered coaches was a run up to Holgate Sidings, just south of York, during which all the various functions of the coaches and DVT were tested - including the door systems during the layover at York.

Of course these trips offered little opportunity to acquire food en route - so if you didn't bring any you starved. The favourite pastime was to bring a frozen meal, bought from Whistlestop at St Pancras and heat it up in the microwave for lunch - practical commissioning!

Click on the picture for a bigger image - pictures are the author's unless otherwise indicated

When they finally entered service we still had to ride shotgun for a few months as there were a few teething troubles to be overcome.

The author well remembers spending the period of the 1990 World Cup on nights at Neville Hill depot in Leeds assisting in fault-finding and maintenance of the Mk 4 coaches - and watching the matches on the Metro Cammell cabin's television.

One problem related to the coaches' air conditioning systems which were subject to extreme failure conditions which either froze or fried the passengers. The problem was exacerbated by the fact that the controls were not accessible from within the coach. This problem was to dog the Mk4 coaches for many years until after privatisation when Angel Trains (the Rosco) finally put some money up and sorted the problem. Ironically we were asked to monitor the performance of the coaches again - ten years on.

This problem became a standing joke and the phrase 'There's always a warm welcome on GNER' was often quoted.

Other problems related to the toilets which suffered from 'blow back' when the train entered a tunnel - no need to go into detail here. The toilet door locks were also a problem since the sliding doors were unable to cope with a determined effort to open them - locked or not. Many an unfortunate passenger was caught on the loo before the problem was overcome.

The coaches were fitted with the Swiss SIG type BT41 bogies and the rode like pigs at 125 mile/h although the bogies had a good reputation on the Continent. For some reason they were not happy on BR track and we had to put up with irate passengers who likened the Mk4's to the Blue Pullman - which had abysmal ride qualities.

The overriding memory of the early service days was rattling round curves like Hatfield with frequent lateral bump stop contact which was described as 'threepenny bit curving'. Eventually after extensive testing and major modifications the SIG bogies achieved an acceptable ride quality on BR tracks.

These mods included changing the bogies' vertical and lateral dampers, alterations to the spring rates of the bogies and the fitting of inter-vehicle dampers. Most unusual of all was the reversing of the bogies (yes turning the bogie through 180 degrees) to reduce the pitch input from the bogie to the coach body) - now if they'd only opted for the T4 BREL bogie ... who knows?

Another problem related to the static inverters which were prone to failure rendering the particular coach without power. The temporary solution was to modify the wiring such that the neighbouring coach could feed a failure, but this was short-lived as the problem was eventually sorted.

Eventually the coaches were modified to overcome their problems but they are still built to a tilting profile making them feel claustrophobic - and for no good reason!!