Drivers across the UK are being urged to be wary of any used car that is fitted with a certain type of engine as it could render the vehicle worthless.
A top mechanic has warned used car buyers over models fitted with a wet belt engine as they are extremely costly to repair and in some cases are completely “unfixable”. A wet belt engine refers to an engine that fully encases the timing belt, meaning it is directly in contact with the engine oil. The oil helps to lubricate the belt, thereby reducing friction and helping to extend its lifespan, but this type of engine is not without its problems.
Wet belts can be more susceptible to issues like belt degradation, oil contamination and accumulation of debris, which can result in expensive repairs.
While wet belt engines are generally more compact and quieter compared to alternatives, the oil can sometimes cause the rubber belt to wear out at a faster rate, so it will need inspecting and replacing more frequently.
In particular, parts of the rubber can flake off thereby increasing the chances of it snapping and causing the camshaft and crankshaft to go out of sync. The rubber debris can also clog up the oil pickup strainer, resulting in engine components being insufficiently lubricated.
Dave Harrison from 911 Auto Repairs in Sheffield urged used car buyers to avoid models fitted with a wet belt engine as they are difficult - and expensive - to fix as the timing belt is sealed within the engine, and in some cases it cannot be repaired at all.
He said: “The next big scandal - wet belts. They replaced timing belts with wet belts on a lot of models after 2017, supposedly they’re more efficient. But the wet belt is a big problem because it only has a 10-year interval and then it breaks.
“It deteriorates and it can stop your brakes working. But if it breaks after nine years, they don’t want to know. And when it does [break], it’s very difficult to fix. It takes twice as long as a normal belt to fix and it costs more to replace.
"That’s one that makes your eyes roll when you see it - oh god, it’s got a wet belt. They say it's better but it ends up costing double to fix or it's unfixable and makes the car basically worthless."
Wet belts were first introduced in 2008 inside the European-market 1.8L Ford diesel engine but various manufacturers have fitted them to their vehicles over the years, with the Ford 1.0-litre EcoBoost being among the most popular in the UK, being fitted to models like the Fiesta, Focus, and EcoSport since 2012, with improvements made in 2019.
Drivers looking to avoid cars with a wet belt engine should also think twice before buying a Peugeot, Citroen, or Vauxhall fitted with the 1.2 PureTech between 2012 and 2023, which also had the problematic engine design.
But when buying any new or used car drivers should keep in mind that even a dry timing belt will still need to be maintained, with manufacturers recommending they be changed every 10 years.