Used BMW 320d engine: how to buy the right unit
To buy the right used BMW 320d engine, match the full engine code stamped on the block, not just "N47", because the 320d badge covers the M47, two main versions of the N47 and the B47, and they do not interchange. Then ask why the donor car was broken, ask what is known about the timing chain, and confirm exactly what comes with the unit. An engine is the most expensive used part most owners will buy, so the checks below are worth the effort. Get the code right and a used unit from a known donor goes in like the original.
Which engine does my 320d actually have?
The 320d name has been used for twenty years across several different engines. The E46 and the first E90 cars up to 2007 used the M47, a conventional chain and belt diesel. From 2007 the E90 switched to the N47D20A, with the timing chain moved to the back of the engine. The 2010 E90 LCI and the F30 from 2012 used the revised N47D20C (often called N47N) with different injectors, a different ECU and more power. From 2015 the F30 LCI moved to the B47. Your registration tells us which you have, and the code is also stamped on the block near the gearbox join. Our engine codes page explains where to look.
| Engine code | Fitted to 320d | Notes |
|---|---|---|
| M47 | E46, early E90 to 2007 | Chain at the front, not interchangeable with N47 |
| N47D20A | E90 E91 E92 E93 2007 to 2010 | Rear timing chain, early chain design |
| N47D20C (N47N) | E90 LCI 2010 to 2012, F30 F31 2012 to 2015 | Revised chain, different injectors and ECU |
| B47 | F30 F31 LCI 2015 on | New engine family, not interchangeable with N47 |
Can I fit an N47D20C in place of an N47D20A?
Not as a straight swap. The two share a basic architecture and many parts, which is why our N47 pistons, camshaft carriers and timing covers list both, but the injectors, high pressure pump, ECU and some sensors differ, and the F30 version has different mounts and ancillary positions from the E90 version. Fitting a C in an A car means swapping or recoding electronics, which quickly removes the saving. Match the full code and, where you can, the body the engine came from: an E90 N47D20C into an E90 is fine, an F30 N47D20C into an E90 needs the E90 ancillaries moved across. If you are unsure, send us your registration and the code off your old block and we will tell you what fits.
What should I ask about the N47 timing chain?
The N47 timing chain sits at the back of the engine against the bulkhead, so replacing it in the car means removing the engine or the gearbox. On the earlier engines the chain and sprockets could stretch and wear, and in bad cases the chain snapped. A good used engine should come with an honest answer about this. Ask whether the chain was replaced, whether the engine was running quietly before removal, and whether the breaker heard any rattle from the rear of the engine. Since the engine is already out when you buy it used, this is the cheapest moment you will ever have to fit a new chain, guides and tensioner, and we recommend budgeting for that on any N47D20A regardless of history.
What should I ask about the donor car?
Ask why the car was broken. An engine from a 320d written off for accident damage or scrapped for an electrical or gearbox fault was running up to the day it came off the road. An engine pulled because it failed should be sold as a block or for parts, and our listings say so when that is the case. We break every car ourselves at our Doncaster yard, so for any engine we list we can tell you the donor model, year, gearbox type and reason for breaking. Our general guide to checking a used engine before you buy covers the physical inspection in detail.
What is included with a used 320d engine?
Check the listing title carefully. A bare block is the block and crank, and on the N47 we often list these separately for rebuilds. A complete engine usually comes with the cylinder head, camshaft carrier, injectors, high pressure pump, inlet manifold and often the turbo, but not the flywheel, clutch or gearbox, and often not the ECU. On a BMW the ECU (DDE) is coded to the car's CAS module and key, so keep your own ECU or buy a matching DDE and CAS kit. Also check whether the engine came from a manual or automatic car, because the flywheel and some sensors differ. If you are not sure what you need, ask before you buy rather than after.
What else should I replace while the engine is out?
Beyond the timing chain on the N47, do the jobs that are only cheap with the engine on the bench: the rear main seal, the sump gasket, the oil cooler seals, the vacuum pump seal and the auxiliary belt, tensioner and idler. Fit a new thermostat and clean the EGR valve and inlet manifold, which carbon up on these engines. Change the oil and filter and prime the turbo before first start. Our guide to engine and gearbox transplants covers the swap itself.
What we usually have in stock for the BMW N47 engine
Stock changes daily, so the BMW N47 engine collection and the wider used BMW 3 Series parts show what is live right now. N47 items we have listed recently include:
- N47D20C engine block, 7811138
- N47N and N47D20C cylinder head, 781260303
- N47 camshaft carrier with camshafts, 11317797511
- N47 timing chain cover, 7797488
- N47D20C high pressure fuel pump, 7810696
- N47 turbocharger (218d, 320d), 8518204
- N47 starter motor, 8506657
- N47D20C 320d engine wiring loom, 851546501
- N47 flywheel gear ring, 779796405
- N47 glow plug wiring harness, 7811162
Complete N47 engines sell quickly, so if one is not showing, send us your registration and we will tell you what is on the shelf or coming in. Fitting a headlight at the same time? See our 3 Series headlight guide.
Buy with confidence
Every engine we sell comes off a known donor car at our Doncaster yard, is inspected before listing and is photographed so you see the actual unit, not a stock image. Tracked UK delivery is included on every order and is free on most parts; panels, engines and gearboxes carry a charge shown on the product page. Order before 2pm on a working day for same day dispatch. If a part is not right, you have 30 day returns. Send us your registration and the part you need and we will confirm fitment before you buy. Parts worth your trust.
Frequently asked questions
Which engine does a BMW 320d use?
It depends on the year. E46 and early E90 cars to 2007 used the M47. From 2007 the E90 used the N47D20A, the 2010 E90 LCI and the F30 used the revised N47D20C, and from 2015 the F30 LCI used the B47. They are not interchangeable, so match the full code stamped on the block and confirm with your registration.
Is the N47 timing chain a problem on a used engine?
It can be. The chain sits at the back of the engine, so it is expensive to replace in the car, and early N47D20A chains and sprockets could stretch and fail. Ask whether the chain was replaced and whether the engine ran quietly before removal. Since the engine is already out, fit a new chain, guides and tensioner before it goes in.
What history should I ask for on a used 320d engine?
Ask why the donor car was broken and whether the engine was running when it came off the road. An engine from an accident damaged car or one scrapped for an electrical or gearbox fault is what you want. We break every car ourselves, so we can tell you the donor's story for any engine we list.
Does a used BMW engine come with the ECU?
Usually not, and you would not normally want it. The BMW engine ECU (DDE) is coded to the car's CAS module and key, so keep your own ECU or buy a matching DDE and CAS kit. Check the listing for what is included: head, injectors, pump, manifold and turbo are common, flywheel and gearbox normally are not.
What if the used engine is not right?
Every order from Partsworth comes with 30 day returns, so if the engine does not match or is not as described you are covered. To avoid the problem altogether, send us your registration and the code from your old block before ordering and we will confirm fitment.