Wightlink Ltd v Mitchell Diesel Ltd (t/a Mitchell Power Systems)

This case concerns the damage caused to the marine port and starboard engines of two high-speed catamarans, which were owned and operated by the Claimant (“Wightlink”) on a high speed passenger ferry service between Portsmouth and the Isle of Wight, called the m/v “FASTCAT SHANKLIN” (“the SHANKLIN”) and the m/v “FASTCAT RYDE” (“the RYDE”).

Wightlink contends that this damage was caused by breach of contract on the part of the Defendant (“MPS”) in its performance between 2003 and 2006 of its overhauls of the engines.

In summary Wightlink’s case is that:

MPS denies that its work caused the engine failures, or that it was defective. In particular, it denies that small clearances between the piston pins and bushes could or did cause the failures. It contends that it was Wightlink’s own poor standards of servicing and maintenance and repairs that caused the vessels’ engines to fail.

Wightlink operates ferry services between the Isle of Wight and the UK mainland. It purchased the RYDE and the SHANKLIN in 2000 and employed them both as passenger ferries on its standard routes. It owns a number of other vessels powered by engines manufactured by MTU including m/v “OUR LADY PAMELA” and m/v “OUR LADY PATRICIA”.

MPS is part of the Mitchell group of companies. It is an authorised distributor for a number of diesel engine manufacturers and provides support for such engines. At the time that it carried out the overhauls of the engines it was an authorised distributor for MTU engines.

The SHANKLIN and the RYDE were constructed in 1996 by Kvaerner Fjellstrand.

After their launch in 1996 they were operated on a ferry service in the Philippines. Wightlink purchased the RYDE and the SHANKLIN in 2000. Prior to their being delivered to Wightlink, MTU’s agents in Cebu, Philippines carried out a scheduled W6 overhaul of the vessels’ engines.

Following their purchase by Wightlink, the vessels were operated on a ferry service between the Isle of Wight and Portsmouth. In 2003 Wightlink determined that their engines each required a scheduled W6 overhaul. It agreed with MPS that MPS should carry out a staged programme of overhauls of the four engines so as to minimise the disruption to Wightlink’s ferry service.

It was Wightlink’s case that the overhauls which were to be carried out were to be W6 overhauls and that MPS was contractually required to follow the MTU Manual requirements in relation to such overhauls. There was no dispute that a W6 overhaul is a major overhaul requiring complete engine disassembly.

By letter dated 2 October 2003 MPS provided Wightlink with a quotation for the overhaul of each of the SHANKLIN’s engines (a cost of £170,219 per engine). This was to include “full overhaul, inspection, rebuild and full Dynotest programme”. Parts which are not routinely replaced during an overhaul but which were unserviceable or missing were to be replaced at cost. The engines were to enjoy a 12 months warranty following the overhaul. The quotation was acceptable to Wightlink and it indicated this by letter dated 23 October 2003.

Although the first of the SHANKLIN’s engines was to have been delivered in the middle of November, 2003, there was a slight delay as Wightlink needed to employ her for slightly longer than originally envisaged before she was taken out of service; this resulted in a slight change to the agreed payment schedule. Ultimately, the port engine (no. 5591660) and the starboard engine (no. 5591661) of the SHANKLIN were delivered to MPS in late December 2003.

The two engines were disassembled, overhauled and then rebuilt by MPS in early 2004. Once this had been completed, it proceeded to test both engines on its test bed. When tested both engines suffered piston seizures which caused damage to the engines. MPS was unable to ascertain the cause of the problem and in March 2004 it arranged for a specialist engineer from MTU (a Mr Heinz Streicher) to assist in identifying and resolving the problems which had been experienced.

The starboard engine (no. 5591661) was tested in his presence, having been rebuilt before his arrival from Germany. It failed on the test bed and was then rebuilt and tested again. On this test, further problems were experienced. Mr Streicher determined that this was consequent upon there being cracks in 13 of the 16 cylinder heads; similar cracks were found in 3 of the cylinder heads in the port engine.

After Mr Streicher’s return to Germany and in the light of his conclusions about the cylinder heads, on 7 April 2004 Mr Lamb of MPS contacted Mr Frampton of Wightlink by telephone and recommended that all cylinder heads be replaced regardless of damage, which he agreed to.

The engines were then disassembled, overhauled and rebuilt again and then tested. They were returned to Wightlink at the beginning of May 2004.

On 13 May 2004 representatives from both MPS and Wightlink met at Wightlink’s offices to discuss the overhauls of the SHANKLIN engines. At this meeting MPS provided Wightlink with service reports for each engine in addition to a number of documents recording certain measurements taken during testing.

Mr Streicher wrote an internal report relating to his visit to MPS which was critical of MPS’ facilities, the training of its personnel and aspects of the overhaul carried out. However, MPS remained and remains an authorised distributor for MTU.

By letter dated 19 October 2004 MPS provided Wightlink with a quotation for the overhaul of each of the RYDE’s engines and the replacement of all 32 cylinder heads. By letter dated 29 November 2004 Captain Frampton of Wightlink confirmed the price and payment terms.

The port engine (no. 5591593) and the starboard engine (no. 5591594) from the RYDE were delivered to MPS on 17 January 2005. The engines were disassembled by MPS who then observed that both required, amongst other things, new engine blocks, the cost of which was not something included in the agreed price for the overhaul. On 25 January 2005, Kevin Draper of MPS advised Captain Frampton that the cost of a new engine block was £45,268.69. By letter dated 2 February 2005 Captain Frampton confirmed Wightlink’s agreement to the purchase of two new engine blocks for the RYDE’s engines at this price.

The engines were then overhauled, rebuilt and returned to Wightlink in April 2005. MPS then provided Wightlink with service department reports for the engines in addition to a number of documents recording certain measurements taken during testing.

On 23 February 2006 the starboard engine (no. 5591661) of the SHANKLIN suffered a catastrophic failure whilst en route from Portsmouth to the Isle of Wight; investigations revealed that the crankshaft had broken. The cause of this failure was attributed at the time to a series of crew errors which had occurred about 5 weeks previously. The engine overheated on 16 January 2006 consequent upon the failure by the duty engineer to open the raw water cooling suction valve prior to departure as it was operated without any (or a severely restricted) sea water cooling flow; it was then, mistakenly, left running at full power; and finally cold water was poured into the overheated engine subjecting it to possible thermal stressing.

The engine was returned to MPS for stripping, investigation and rebuilding. By letter dated 10 April 2006 Mr Winterman of MPS provided a quotation for a further unscheduled W6 overhaul of it and the replacement engine components required. This was accepted by Wightlink and MPS proceeded to disassemble, overhaul and rebuild the engine. It was returned to Wightlink and re-installed on the SHANKLIN in May 2006.

On 22 July 2006 the port engine (no. 5591660) on the SHANKLIN suffered a catastrophic failure while the vessel was proceeding from the Isle of Wight to Portsmouth. It was subsequently established that the no. 6 unit of the A-bank of cylinders on the engine had failed.

The engine was removed from the SHANKLIN and returned to the manufacturers, MTU, in Duisburg, Germany for inspection and repair. This process was overseen by Mr Josef Grote of MTU. A report on MTU’s inspection of the disassembled engine, identifying the defective parts and the requirements for repair or replacement of the various components was prepared. It noted that the Conrod bushings were far below the MTU specified dimensions:

“Bushings far below specified dimensions. Actual 60.010 – 60.040

Spec.: 60.070 – 60.080, all bushings with clearly visible wear traces – replace by new part and drill to dimension”

MTU carried out a W6 overhaul. The failed piston, liner and associated components from cylinder A6 were examined by metallurgists Materials Technology Limited who produced a report dated 27 September 2006. They concluded that the likely cause of the failure was metal fatigue. In the light of this report as well as the various other reports in existence at the time, Casebourne, Leach & Co., consulting marine engineers and ship surveyors, determined in a report to average adjusters dated 23 October 2006, that of two suggested possible causes for the failure the more likely was incorrect machining of the piston gudgeon bushes.

MTU subsequently produced a written “Damage Scenario” setting out its Duisberg workshop’s view as to the likely cause of the failure of the engine. This was provided to Wightlink at the end of November 2006. It stated that the suspected reason for the damage was that:

“the necessary clearance between piston bolt and bushing was minimal

minimal clearance would cause high reaction forces between liner wall and piston crown due to restricted movement of piston at reversal points...”

On 8 November 2006 while on passage from Ryde to Portsmouth, the lubricating oil alarm on the RYDE’s port engine (no. 5591593) sounded and the engine stopped. The vessel continued to Portsmouth on her starboard engine. Following investigations and removal of the cylinder head on unit no. B8 it was apparent that a catastrophic failure of the piston had occurred which rendered the engine unfit for continued service without major repairs.

The port engine (no. 5591593) was removed from the RYDE and returned to MTU, in Duisburg, Germany for inspection and repair. In addition, as a consequence of its increasing concerns about the overhauls which had been carried out by MPS, Wightlink decided to remove the starboard engine (no. 5591594) from the RYDE at the same time and to return it to MTU for inspection and, if necessary, repair.

The inspection of both engines was overseen by Mr Grote. A report on MTU’s inspection of the disassembled port engine (no. 5591593), identifying the defective parts and the requirements for repair or replacement of the various components was prepared dated 14 December 2006. In the Inspection Report the following was recorded as regards the Conrods:

“B8 conrod/B8 piston were damaged by torn-off piston crown. All other conrods had undersized piston pin bores (by 0.03-0.04mmtoo small) and axial parallelism and twist were clearly out of tolerance.”

A similar report was prepared for the starboard engine (no. 5591594) dated 20 December 2006.

As with the SHANKLIN port engine, it was decided that the engine required an unscheduled W6 overhaul. It was also decided that the condition of the starboard engine (no. 5591594) of the RYDE (although it had not yet suffered a catastrophic failure) was such that it also needed an unscheduled W6 overhaul. As was recorded by C.W. Molyneux, the surveyor appointed by underwriters to investigate the damage caused to the engines following his attendance at MTU’s premises for a survey on 16 January 2007:

“Several issues have been highlighted by MTU in Germany that may be related to the most recent W6 overhaul, notably the gudgeon pin / bush clearances...Please note that as a precaution the Owners had the starboard engine removed and sent MTU, Duisburg, for inspection. Conditions similar to those discovered on the port main engine have been discovered and once again the gudgeon pin/bush clearances have been found to be below manufacturers tolerance.”

Shortly after the W6 overhaul carried out by MPS in the spring of 2006 and the SHANKLIN returned to service, the lubricating oil pressure was noted by Wightlink to be abnormally low. MPS was advised of Wightlink’s concerns and they both sought to resolve the problem. Wightlink changed from a synthetic oil in service to a regular mineral oil. In addition, the fuel pumps were removed and sent to Bosch to be pressure tested where it was discovered that the high pressure non-return valves were leaking; repairs were carried out and the pumps refitted. Nevertheless, samples of lube oil drawn from the engine in early 2007 exhibited excessive soot. In the absence of a solution to the problem and concerns consequent upon the condition of the other engines, in April 2007 Wightlink determined to remove the SHANKLIN starboard engine (no. 5591661) and return it to MTU for inspection and, if necessary, repair.

MTU’s inspection report dated 6 February 2007 noted amongst other matters that:

“14 conrod bushings were drilled to far below the tolerance (spec.: 60.070 – 60.080 / act.: 60.030 – 60.050).”

As with the other three engines inspected by MTU, the SHANKLIN starboard engine (no. 5591661) was in a condition which it was considered required a complete W6 overhaul, which was duly carried out.

Wightlink’s claim is for the cost of the removal and repair of the four engines together with some storage charges. The total sum claimed by Wightlink is £1,397,959.10.

At the trial I heard factual evidence from the following witnesses for Wightlink:

I heard evidence from the following factual witnesses for MPS:

In addition I heard expert evidence from Mr Ian Head for Wightlink and from Mr John Blowes for MPS, consultant marine engineers.

There were major differences between the experts in relation to the central issue in dispute, namely the cause of the engine failures. Mr Head was adamant that these were due to the fact that there was insufficient clearance between the piston pins and the bushes. Mr Blowes was equally adamant that this was not and indeed could not be the cause, and that the explanation lay in poor servicing and maintenance by Wightlink.

The principal issues which fall to be determined are as follows:

What duties did MPS owe to Wightlink?

The contracts between the parties are contained in or evidenced by the quotation and acceptance letters of October 2003 (for SHANKLIN), November/December 2004 (for RYDE) and the quotation letter of 10 April 2006 (for the SHANKLIN starboard engine overhaul). Although there had been an agreement in principle prior to October 2003 that MPS would carry out a staged programme of overhauls, there was no contractual commitment that this be done and each overhaul was separately contracted for.

The letters for the SHANKLIN and RYDE overhauls describe the service contracted for as being the “overhaul and rebuild” of the engines which was to include “full overhaul, inspection, rebuild and full Dynotest programme”. They do not state that this is to be a W6 service. By contrast, the April 2006 letter for the SHANKLIN starboard engine overhaul did provide a quotation “to perform a W6 overhaul on the engine and replace additional components required to bring the engine back to an operational condition”.

The parties were aware that the engines were MTU engines and that the MTU “overhaul and rebuild” service is the W6 service. It was understood that the service would be carried out by reference to the MTU Manual for W6 services but, save in respect of the SHANKLIN starboard engine 2006 overhaul, there was no contractual agreement to perform a W6 service.

Wightlink contended that not only was it contractually agreed that MPS would perform a W6 service but also that this meant that the terms of the Manual were incorporated into the contract so that strict compliance with the Manual was contractually required.

Wightlink placed particular reliance upon the statement made in the Manual that a W6 overhaul:

“Requires complete engine disassembly to facilitate repair/overhaul of all relevant components. The decisive factor is the component condition or the actual dimensions, referenced to the Tolerance and Wear Limits List.”

It was submitted that this required strict compliance with the Tolerance and Wear Limits specified by MTU in the re-built engines.

In relation to the SHANKLIN and RYDE overhauls there was, however, no contractual agreement that the overhaul would be a W6 service. Further, in relation to none of the overhauls was there an express agreement that the W6 Manual was to be incorporated in or followed as a matter of contract. Nor in my judgment can such an agreement be inferred from the terms of the Manual or otherwise.

The opening words of the Manual read: “the tolerances and wear limits indicated in this publication are intended as a guide for the examination of engine components during inspection and repair.” As this indicates, and as would be expected, the Manual is a guide; it is not drafted as a contractual specification and nor would it easily so function.

As Hobhouse J stated in Alexander & Ors v Standard Telephones and Cables Ltd (No 2) [1991] IRLR 286 at [31]:

“The fact that another document is not itself contractual does not prevent it from being incorporated into the contract if that intention is shown as between [the parties]. Where a document is expressly incorporated by general words it is still necessary to consider, in conjunction with the words of incorporation, whether any particular part of that document is apt to be a term of the contract; if it is inapt, the correct construction of the contract may be that it is not a term of the contract. Where it is not a case of express incorporation, but a matter of inferring the contractual intent, the character of the document and the relevant part of it and whether it is apt to form part of the individual contract is central to the decision whether or not the inference should be drawn.”

There was no express incorporation of the Manual in this case, nor is it apt to form part of the contract. The Manual recognises, for example, that "work listed here which is not relevant to the respective engine equipment can be disregarded" and that "specific operational conditions may require modification of the Maintenance Schedule”. Further, in some instances, it would be impossible for MPS to abide by the Manual tolerances as many of the parts were supplied pre-machined by, and in some instances to tolerances outside of their own guidelines. Moreover, what was being sought and provided was a highly bespoke and intricate service, with adjustments and refinements as were specifically required, but also in many instances with discussions about what parts might be needed anew with consequent cost consequences. On occasion, for example, Wightlink refused to have certain new parts, so the Manual dimensions were of no application.

For all these reasons I reject Wightlink’s contention that the Manual was contractually incorporated and that there was any contractual requirement that the Manual be strictly complied with.

On the other hand it was common ground that MPS owed duties as a matter of contract to exercise reasonable skill and care in and about all work and servicing carried out by it and that all components replaced or reconditioned would be of satisfactory quality and fit for use within the particular engine. I accept that this meant that in carrying out the overhauls MPS had to have regard to the MTU Manual, including its Tolerance and Wear Limits. This was a MTU engine. The MTU Manual sets out in detail how a major overhaul involving disassembly, inspection and rebuild of such an engine should be carried out. That was the obvious and only specifically relevant reference document for such an overhaul. The Manual should therefore have been used as a reference point. However, there was no requirement that it be strictly complied with.

Was MPS in breach of its duties to Wightlink?

According to the Tolerance and Wear Limits Manual, the clearance between the piston pins and the piston pin bushes were stated to be a minimum of 0.070mm and a maximum of 0.085mm.

Judged against that criteria, I find that the clearances between the piston pins and the piston pin bushes were undersized in almost every cylinder of all four engines. This is clearly evidenced by the data sheets prepared by MTU, Duisburg, Germany when it dismantled the engines and was supported by the evidence of Mr Grote. Mr Blowes questioned some of the smaller recorded measurements on the grounds that such clearances would have been difficult if not impossible to achieve and would have made assembly of the unit problematical. However, I accept the measurements as being broadly accurate and as clearly establishing clearances below the minimum stated in the Manual. MPS also sought to cast doubt on the figures by suggesting that there was no satisfactory documentary evidence of the diameter of the piston pins. However, I accept Mr Head’s evidence that, save for the exceptions noted or accepted by him, all of the pins were of 60 mm diameter or so close thereto as to make no material difference.

Indeed, it was MPS’ evidence and case that they deliberately machined the bushes with smaller clearances in accordance with common industry and their own standard practice. Their machinist, Mr Ratcliffe, explained that they would aim for a constant running clearance of 0.025 to 0.038 mm. This practice is described as selective machining.

Wightlink’s expert, Mr Head, accepted that provided selective machining is properly carried out it is acceptable practice. If, for example, MPS had carried out selective machining with the aim of achieving a clearance of between 0.070mm and 0.085mm that would be unobjectionable. In his opinion, however, what was unacceptable was selective machining to a different and lower clearance than that specified by MTU. MPS’s expert, Mr Blowes, disagreed. It was his opinion that selective machining to the clearances identified by Mr Ratcliffe was not only acceptable and widely followed practice, but was preferable in terms of both engine wear and noise.

I shall address below in the context of the issue of causation the technical justification for and effect of machining to these lower tolerances. Whether so doing involved a breach of the duty of reasonable skill and care will therefore be considered further once the issue of causation has been addressed.

Did MPS’s breaches of duty cause the engine failures and/or the damage to or defects found within the engines?

Whether the small clearances between the piston pins and bushes caused the engine failures and other defects found in the engines was the central issue in the case.

Wightlink’s expert case was that the small clearances restricted free movement of the connecting rods as they oscillated which in turn restricted the linear movement of pistons up and down the cylinder liners, which in turn forced the pistons against cylinder liners resulting in high reaction forces and increased loading between them, particularly at the piston reversal points. This then caused metal fatigue leading to the engine failures.

MPS’ expert case was that this did not and indeed could not have caused the failures and that the most likely cause was poor operation and maintenance of the engines by Wightlink.

In support of Mr Head’s theory of damage, Wightlink relied in particular on the following:

Mr Blowes put forward a raft of reasons as to why Mr Head’s theory could not explain the damage. In particular, he stressed the following:

Both parties made veiled attacks on the independence of the other’s expert witnesses. However, I am satisfied that both experts were seeking to assist the court and give independent views.

There was, however, a contrast between the experts. Mr Head was an ex Salvage Association surveyor with considerable general experience which included but was not limited to diesel engines. Mr Blowes was a diesel engine specialist, albeit much of his experience was land based.

Mr Head would appear to have formed a fixed view at a relatively early stage that the cause of the failures must be the small clearances. He made it clear that he had made his mind up and rejected principles put to him on the basis that they did not fit his theory of what happened. He was also inclined to dismiss matters put to him as being theoretical or derived from textbooks, even if he accepted the principles involved. His evidence was very much that of the practical man but he found it difficult to back his conclusions with analysis, established theory, empirical data or similar examples. With regard to the one textbook upon which he did seek to place reliance he quoted a section that related to main bearings rather than small end bearings and eventually had to accept in cross examination that it was not relevant.

Mr Blowes, by contrast, explained the engineering principles which underlay his opinions and backed it up with detailed analysis and examples. His approach both in his reports and evidence was far more methodical and analytical than that of Mr Head.

Having carefully considered the factual and expert evidence I have come to the clear conclusion that Mr Head’s theory of damage must be rejected. I found the evidence of Mr Blowes to be far more convincing on this issue for the various reasons given by him and in particular the following:

Mr Head repeatedly returned in evidence to the point that if the engine manufacturers recommended a particular clearance then it must be necessary. However, he was unable to explain why it was necessary, nor was there any technical evidence from MTU to explain this. Nor was he able to explain at what point and why the lack of clearance would become critical. In his supplementary report he developed a theory that the reason for the recommended clearances was because of unusual oil feed arrangements which would have reduced the oil flow around the pin. There was no evidence from MTU to this effect, nor was it raised with Mr Grote. Moreover, I accept Mr Blowes’ evidence that the oil feed arrangement was not unusual and that in any event there were ample sources of oil. Further, as Mr Head accepted, for lubrication purposes only a small film of oil is required and Mr Head’s theory was based on lack of lubrication, not lack of cooling or cushioning.

In relation to the main points relied upon by Wightlink I find as follows:

Even if it is technically justifiable and acceptable engineering practice to machine to these smaller clearances a question potentially arises as to whether a reasonably competent engine workshop would do so without first consulting MTU given that it was contrary to their Manual recommendations. There was some evidence from Mr Draper and Mr Blowes which would suggest that this should be done and one can well understand that it would be good practice to do so. However, Wightlink did not plead or advance their case in this way nor were the causation issues which would arise explored in evidence. In these circumstances I do not consider that it would be appropriate to make any finding on this issue; the issue is one of negligence and any such case should be clearly identified in advance of the evidence.

If, contrary to my findings above, the adoption of small clearances did involve a breach of contract I reject Wightlink’s case (advanced for the first time in closing submissions) that this breach was an effective cause of the losses claimed even if it did not cause the engine failures. Wightlink sought to argue that the fact that the small end bushes were significantly undersized in each engine was in itself good reason for Wightlink to effect a full W6 service on each of the engines. However, the reality is that the engines were removed because of the failures which had occurred. Indeed that is Wightlink’s own pleaded case in relation to the removal of the RYDE port engine. Although, advice was given to remove the other engines because undersized clearances were likely to be a common feature of the overhauls, that advice was given in the light of the failures which had occurred and the fact that these had been wrongly assumed to be attributable to the small clearances. So, for example, if the small clearances had been identified at the time of the SHANKLIN starboard engine overhaul in May 2006, following the failure ascribed and due to crew negligence rather than overhaul issues, I have little doubt that it would not have been said that this necessitated the removal of all the other engines, nor would this have been done.

Wightlink also sought to rely on a number of alleged breaches of duty in relation to the overhauls carried out by MPS (“the secondary case”). These were not explored in any detail in the argument or the evidence. The reason for this is no doubt because these were not alleged to be causative of the engine failures or of the consequent need to remove and disassemble the engines. In relation to the SHANKLIN port engine the only pleaded cause of the failure was insufficient clearances. In relation to the RYDE port engine there is also a reference to the piston pins not being parallel to the crankshaft but Mr Head never suggested that this was causative and Wightlink’s counsel accepted in opening that its case was that the cause of the failures was insufficient clearances and not other issues. As to the other engines, the Particulars of Claim asserts that “as a consequence of” the failure of the RYDE port engine the starboard engine was removed, which involves an averral of the same underlying cause. Although the other engine failures are not expressly pleaded as being the reason for the removal of the SHANKLIN starboard engine, there is little doubt that they were and I so find.

In these circumstances Wightlink’s secondary case is of no causal relevance since it is not contended that the alleged breaches caused the engine failures or the removal of the engines. It is possible that some of these alleged breaches led to increased repair costs but it was not pleaded or alleged in evidence that they resulted in any particular or separately identifiable loss and damage. Wightlink’s case was put globally in relation to the entirety of the repair costs and it must stand or fall on that basis.

It is therefore not necessary to address Wightlink’s secondary case in any detail, nor was it so addressed at trial. The pleaded breaches were as follows:

Mr Head expressed the opinion in his reports that these alleged defects would all be attributable to “inappropriate servicing” by MPS. This was disputed by Mr Blowes. Although Mr Blowes accepted in cross examination that it was possible that MPS was responsible for some of the alleged defects he did not accept that they were. Proof of breach of contract in relation to these alleged defects called for more than the cursory treatment which they received in the evidence and at trial. Bearing that in mind, and Mr Blowes’ evidence in his reports and in cross examination as to why MPS fault was not necessarily involved, I am not satisfied that the further alleged breaches have been proved on the evidence with the exception of the wrongly located relief valves on the SHANKLIN starboard engine. However, there is no proven loss as a result of that breach of duty.

Was it reasonable to repair the engines and should the quantum of the claim be reduced for betterment?

The costs claimed associated with the breakdown, removal and repair of the port and starboard engines from each of the SHANKLIN and the RYDE were as follows:

MPS contended that (1) the repair costs were not reasonable and (2) the repaired engines represent betterment for which the Claimant is not entitled to claim or for which credit must be given.

In relation to (1), these represent the MTU overhaul costs which costs have already been the subject of an average adjustment. No specific points were made by MPS in respect of any particular item or items of cost incurred. They simply relied on Mr Blowes’ generalised evidence as to the expected overall cost of such an overhaul. That is not sufficient basis for challenging this detailed and already adjusted claim. I find that the costs claimed are reasonable.

In relation to (2), it is well established that no deduction is to be made from damages if there is necessary betterment due to repair – see Halsbury’s Laws, Vol. 12(1) (Reissue) 4(2)(i), para. 862 and 5(1)(v), para. 983; also Bacon v Cooper (Metals) Ltd[1982] 1 All ER 397. The evidence was that if an engine has to be disassembled then it needs to be reassembled in accordance with W6 requirements. That is what was done. No attempt was made to seek to show that a particular replacement or repair carried out on that basis was unnecessary or unreasonable. No betterment case has been proved.