Serpentine drive pulley failure

The consumer’s issue:

“I bought a used 66-plate executive car in April 2020, and a warranty policy costing £1,800 to cover any mechanical faults. On 15th October 2021, I was sat in traffic and heard a bang from the engine, and the alternator and water pump failed suddenly.

It was later discovered that the serpentine drive pulley on the end of the crankshaft had actually failed. However, the warranty company claimed that, because the pulley had rubber components, it would have deteriorated over time, and would therefore not be a sudden breakdown, meaning it was down to wear and tear. I disagree with this conclusion, because in my view, this was a sudden unexpected breakdown.

I therefore had to pay for the cost of repair myself, but I believe I should be refunded the £798 I paid for the work, as this is not a wear and tear component. The pulley is in a non-accessible area of the engine and is not subject to periodic checks or replacement.”

The accredited business’ response:

  • We received a call from the consumer on 18th October 2021 regarding a fault with their vehicle, and a claim against the warranty policy they held with us.
  • The repairer contacted our claims team on 27th October, and reported that the crankshaft pulley rubbers had collapsed.
  • We declined the claim, because in our view, the rubbers would have deteriorated over a period of time, and therefore were not deemed to be a sudden mechanical failure, which is what is covered by the policy. In our opinion, the rubbers in the pulley had failed because of wear and tear.
  • We believe we acted correctly in declining the claim in accordance with the consumer’s policy terms and conditions.
  • As such, we dispute the fact that we have any obligation to cover the customer’s cost of the repairs to their vehicle.

The adjudication outcome:

  • The Motor Ombudsman adjudicator explained that the consumer had the evidential burden of showing that the fault with the crankshaft pulley rubber was covered by the warranty agreement.
  • The adjudicator reviewed the evidence and representations provided by both sides, which included photos of the component, notes from the conversations that had taken place, as well as the terms and conditions of the policy.
  • The adjudicator pointed out that the terms and conditions stated that that there must be a mechanical breakdown for the policy to be activated and the protections applied.
  • The adjudicator noted that, although the consumer had experienced a sudden event which brought the fault to their attention, this was not sufficient evidence in itself that the crankshaft pulley rubbers had failed suddenly owing to a mechanical breakdown, rather than being due to wear and tear.
  • Therefore, because there was insufficient evidence of a mechanical breakdown, the warranty provider did not have a contractual obligation to cover the repair costs, or refund the warranty policy payments to the consumer.
  • As a result, the adjudicator did not find a breach by the accredited business of the Vehicle Warranty Code and concluded that they could not uphold the case in the customer’s favour.
  • The adjudicator recommended that the consumer obtain independent technical evidence to support their assertion that the failure to the rubber pulley was due to a sudden mechanical breakdown.


  • No further response was received from either party. Therefore, the adjudicator closed this case once the timeframe to respond had passed.