BMW N47 Timing Chain Failure: Symptoms, Replacement and Tools

October 30, 2026

BMW N47/N57 diesel timing tool kit with camshaft setting plate and flywheel locking pin

The timing chain is the N47's best-known weakness. BMW put the chains at the back of the engine, on the transmission side. Owners usually hear a rattle long before anything breaks. When the chain does break, the engine stops dead and the valves, rockers and camshafts often take the damage. If you own a 118d, 120d, 320d, 520d, X1 or X3 2.0d from the late 2000s, it pays to know the warning signs and what the repair involves. This guide covers the symptoms, which cars are affected, why the chain fails, the parts to buy, and the BMW N47/N57 diesel timing tool kit that locks the engine in time while the chains are off.

Signs of N47 Timing Chain Trouble

A rattle or whirring from the rear of the engine, near the bulkhead and bellhousing. It is usually loudest on a cold start and gets worse over time.
Noise that changes with engine speed rather than road speed, so it is still there in neutral
Worst case: the engine cuts out while driving, sometimes at speed, and won't restart

The rattle is the warning. Don't ignore it or drive the car "until it gets worse". Once the chain breaks, a chain kit is no longer enough: you are looking at head work, a used engine or a full rebuild.

Which Cars and Engines Are Affected

The 2.0-litre four-cylinder N47 diesel was used from 2007 into the mid-2010s across the 1 Series (E81/E82/E87/E88 and F20), 3 Series (E90–E93 and F30/F31), 5 Series (E60/E61 and F10/F11), X1 (E84), X3 (E83) and the 2 Series F22. That covers the 116d, 118d, 120d, 123d, 316d, 318d, 320d, 520d, X1 sDrive20d/xDrive20d and X3 2.0d/xDrive20d. Engines built from March 2007 to January 2009 are generally considered the worst affected, although failures have been reported on later engines too.

The six-cylinder 3.0-litre N57 also has its chains at the rear of the engine, but failures are reported far less often. The same diagnosis applies: noise from the back of the engine means it needs a closer look.

Always confirm the engine code on the block or from your VIN before ordering parts. Later B47/B37 diesels need a different B37/B47 timing chain tool kit.

Why the Chain Fails

The N47 uses two chains. The lower chain drives the high-pressure fuel pump, and the upper chain drives the camshafts. Both depend on a hydraulic tensioner and plastic guides. Common causes include:

Guide and tensioner wear. As the guides wear and the tensioner loses control, the chain slaps and stretches.
Oil quality and intervals. The chain depends on constant clean oil. Long service intervals, the wrong oil spec and low oil levels all speed up wear.
Driving pattern. Lots of short trips are often linked to early wear.
Design and machining. BMW revised the parts during production. Some specialists report that the drive gear on early engines was machined into the crankshaft itself, so a badly worn crank gear can mean a new crankshaft.

Parts to Buy

Replace the whole timing set, not just the chain. A complete N47 kit, such as febi 102040, includes:

Upper and lower chains
Chain guides and the hydraulic tensioner
Camshaft sprockets and the high-pressure fuel pump sprocket
The lower chain oil spray nozzle

You will also need a timing case seal, a rear crankshaft seal, an oil filter, oil and coolant. If the chain has already broken, budget for rockers, the camshaft carrier, possibly camshafts, and head bolts if the head comes off. Plan to inspect the clutch and flywheel while they are out, since you have to remove them anyway.

Tools You'll Need

Diesel Timing Tool Kit for BMW N47/N57: a camshaft setting plate, flywheel locking pin, crankshaft turning tool and HP pump sprocket retaining tool, for N47/N47S/N57 engines (codes D20A, D20B, D20T0, D30U0 and D30T0). The listed fitment is the 118d, 120d and 123d (E81/E82/E87), 318d and 320d (E90/E91/E92), 520d (E60/E61) and X3 2.0d (E83).
An E-Torx socket set for the external Torx bolts used throughout the bellhousing, flywheel and timing case. Our Torx, E-Torx and XZN guide explains which bit goes where.
An adjustable click-type torque wrench. Many fasteners on this job have specific torque or torque-plus-angle specs.
A 32 mm open-end spanner for the hex on the exhaust camshaft
An engine crane, an engine stand or support, a transmission jack, and a scan tool for clearing faults afterward

The Job, Step by Step

Because the chains sit at the transmission end, the engine has to come out. This is an overview of the order of work, not a substitute for the factory procedure and torque specs.

Remove the engine. Drain the fluids, disconnect everything, and lift the engine out. Then separate the transmission and mount the engine where you can work on the back of it.
Lock the crankshaft. Remove the clutch, then fit the flywheel locking pin to hold the crank at its timing position. Rotate the engine only with the crankshaft turning tool, never by the cam or pump sprockets.
Set the camshafts. Remove the cam cover and fit the camshaft setting plate. If the cams aren't sitting exactly at their timing position, stop and find out why before going further.
Strip the timing case. Remove the flywheel, the sump and the timing case cover. Inspect the chains, guides and sprocket teeth. On a failed engine, check for bent valves, broken rockers and a cracked cam carrier.
Remove the old timing set. Use the HP pump sprocket retaining tool to hold the high-pressure pump sprocket, then remove the tensioner, guides and both chains.
Fit the lower chain and guides. Pay attention to the fitting direction of the lower chain and oil pump sprocket. Clean the tensioner's mating face on the block before installing it.
Fit the upper chain and tensioner. Apply threadlocker to the upper guide bolts as specified. Pull the tensioner's locking pin only once both chains are in place.
Check the timing. With the crank pinned and the setting plate fitted, confirm the cam marks line up. You can turn the exhaust cam slightly on its hex with the 32 mm spanner to correct alignment. Torque the sprocket bolts to factory spec.
Turn it by hand. Remove the locking tools and rotate the engine two full turns with the turning tool. Refit the tools and confirm everything still lines up.
Reassemble and refit. Fit a new timing case seal and crank seal, then refit the flywheel, clutch and transmission. Install the engine, refill the oil and coolant, clear the faults and road test.

For other BMW timing jobs, see our N20/N26 timing chain and flywheel guide or browse the BMW N-Series collection.

Common Mistakes

Replacing only the chain. Worn guides and a tired tensioner will wear out a new chain quickly. Replace the full set.
Skipping threadlocker on the upper guide bolts. These bolts can back out in service.
Over-tightening the camshaft bearing bracket bolts. The carrier is easy to crack. Use the factory figure and a torque wrench.
Not oiling the camshaft bearings before reassembly
Using the timing tools to hold the engine while you loosen or tighten big bolts. Locking pins set position. They aren't meant to take breaking torque.
Fitting a cheap used engine without a warranty that covers the chain. It may have the same problem.

Frequently Asked Questions

What does a failing N47 timing chain sound like?

It is usually a rattle or whirring from the back of the engine, near the bulkhead and bellhousing. It is often loudest on a cold start and gets worse over weeks or months. It follows engine speed, not road speed, so it is still there in neutral. Treat it as a warning to act before the chain breaks and the engine cuts out.

Does the engine have to come out to replace the N47 timing chain?

Yes, in practice. On the N47, BMW placed the timing chains at the rear of the engine, on the transmission side. To reach them you remove the engine, separate the transmission, and take off the clutch, flywheel, sump and timing case. That is why the job is expensive at a shop, and why it pays to replace the full timing set while you are in there.

Which BMW models have the N47 timing chain problem?

The 2.0-litre N47 diesel was used from 2007 in the 1 Series (116d, 118d, 120d, 123d), 3 Series (316d, 318d, 320d), 520d, X1 (E84), X3 2.0d (E83) and later F-chassis cars. Engines built from March 2007 to January 2009 are considered the worst affected, though later engines have failed too. The 3.0-litre N57 fails less often.

What does the N47/N57 timing tool kit do?

It holds the engine in its timing position while the chains are off. The camshaft setting plate holds the camshafts, the flywheel locking pin holds the crankshaft, the turning tool rotates the crank for checks, and the HP pump sprocket tool holds the fuel pump sprocket. It is listed for N47, N47S and N57 engines in the E81/E87, E90, E60 and E83 models.