BMW & Mini Timing Chains

Timing Chain Replacement - Timing Chain Failures - Timing Belts

The rhythm of your engine

Timing Belts and Timing Chains are an essential part of your engine, when they fail on a modern German engine you should bear in mind that the small cost to replace a chain or belt is minor in comparsion to the price of rebuilding your engine.

Cam timing is set to decide when the valves open and close in relation to the position of the pistons within their bores. The settings are determined when the engine is built from the relationship between camshaft and crankshaft. The timing needs to be constant and accurate to avoid significant engine damage.

Timing Works

Timing Belts / Cambelt

It's best to replace your timing belt once every 3 to 4 years. Remember that we're referring to a simple rubber belt no more than an inch wide that is continously rotating around metal pulleys and tensioners.

Mileage cannot be relied on for reassurance that a belt, pulley or tensioner won't fail, resulting in complete engine failure.

Timing Chains

Typically used by BMW, Mercedes and on later VW/Audi, Ferrari & Maserati Engines. Service intervals are typically over 100,000 miles but on certain engines it's a lot earlier due to design flaws not admitted to by manufacturers. It is usually a tensioner failing that causes chain stretching and links breaking usually leading to catastrophic engine failure.

Timing Chain Rattle

If you hear a rattle from the engine bay which is particularly loud on startup and you suspect that it could be your timing chain, don't ignore it - take no chances, get it checked for free at Dragon Automotive.

Consider it lucky if you do hear a rattle as you could save your engine. Rebuilds tend to up to three times the cost of a timing chain replacement.
Screenshot

BMW N47 Timing Chain Failure

Don't let the chain kill your engine

It has been well documented that there is an ongoing issue with BMW N47 Engine timing chain failures.

A simple google search will provide reems of information and the BBC watchdog investigation into the problem. The simplex chain used by BMW in their engines is just not proving to have the longevity expected of timing chains. The extended service periods reduce the oil quality as well which affects the chain lubrication.

In our experience, We replace more BMW chains than any other brand of engine. Not just the common N47 and N57 Diesel engines but more or less the entire range for one reason or another.