The controversial new diesel loco has still got teething problems - despite being fitted with a replacement engine.
Further problems came to light during test runs last week carried out after engineers from US firm Cummins fitted a replacement engine.
Director of public transport Ian Longworth said the issue now appeared to be the air intake temperature and new parts had been ordered. These have now been fitted.
The Examiner reported in January that just weeks after being shipped over to the island by its American manufacturers, the £400,000 loco had been ignominiously consigned to the engine shed at Douglas awaiting repairs having failed during initial trials.
Colin Kniveton, then chief executive of the now disbanded Department of Community, Culture and Leisure, said at the time that diesel no.21’s engine had overheated when tested under load.
But asked for an update, Mr Longworth insisted the engine had never overheated. He said the original engine had ‘shown distress possibly due to manufacturing defect’.
He said the test programme was due to be completed this week but the new engine had shown the ‘air temperature at turbo intake was higher than was desirable’.
As a result, he said, Cummins had recommended a different combination of air intake and filtration. ‘Both the existing and ordered air intake are Cummins standard options and parts,’ he said.
‘The engine is still instrumented and further test runs will be required to fine tune the performance of the engine in due course,’ he added.
The Examiner understands, however, there is a problem with cooling and the climb out of Douglas station up Nunnery bank.
The work is being carried entirely at the expense of the loco manufacturers Motive Power and Equipment Solutions and its subcontractor Cummins Atlantic US.
Mr Longworth said given the contractual position, ‘public comment and speculation by me is not helpful to getting matters resolved between them’.
He said: ‘On the original test programme the engine showed distress on the full load test as a result of which Cummins have provided a replacement engine. Interestingly neither the old or new engine has ever been allowed to overheat.
‘The distress the original engine showed means in my opinion it was and still is the correct decision by Cummins to replace.’
The problems with the green diesel loco will come as a continuing embarrassment for public transport bosses who had claimed the machine would pay for itself in 13 years and help make savings of almost £40,000 a year, designed to be used to rescue broken down trains and to also be called on to deal with lineside fires and shunting duties.