Water in Oil — Who Is Liable When a Workshop Causes Oil Contamination?

When a Workshop Is at Fault

Oil contamination can be caused by workshop error. Common scenarios include: using the wrong type of fluid during a service; failing to properly seal a drain plug or filler cap allowing water ingress; incorrectly fitting an oil cooler or gasket; or allowing coolant to enter the oil system during a cooling system repair. If contamination arose following a service, the workshop may bear full liability.

Your Legal Rights

Under the Consumer Guarantees Act, services must be performed with reasonable care and skill. If a workshop performed a service that caused or failed to detect contamination that a competent mechanic should have found, you have rights against them. You can seek compensation for: the cost of the oil manufacturer-spec fuel system recovery; consequential engine damage caused by the contamination; the cost of alternative transport; and any economic loss.

Building Your Case

Documentation is critical. Get EEK Mechanical's Oil Contamination Report before the vehicle returns to the workshop — this establishes the contamination state objectively and independently. Keep all invoices from the workshop that performed the prior service. If the workshop disputes liability, use the Disputes Tribunal (for claims up to significant cost) or seek legal advice for larger claims.

Evidence EEK Mechanical Provides

Our Oil Contamination Report is an independent technical document accepted by the Disputes Tribunal and Motor Vehicle Disputes Tribunal. It confirms: contamination type; severity; likely source; evidence of mechanical failure; and our assessment of whether the contamination is consistent with a service-caused event.