Introduction

From 2007 to approximately 2014, the BMW N47 was an inline 4-cylinder diesel motor that was employed in the BMW 1, 2, 3, and 5 collection, as well as the X1 and X3 diesel styles.

The N47 engine series is prone to early timing chain failure owing to critical timing chain use. The problem is indicated by a rattling sound coming from the engine’s rear. Failure of the timing chain could necessitate motor substitution or a expensive restore. The difficulty has an effect on all purposes and energy versions of the motor created involving March 1, 2007 and March 1, 2011. The most seriously destroyed units, which need the most considerable repairs, had been made involving the dates of 01.03.2007 and 05.01.2009. UPDATE – It appears that a smaller range of engines manufactured just after the remember are getting problems.

Timing chain

The timing chain on this motor is sandwiched in between the motor and the transmission at the back of the motor. Its substitute is especially challenging for the reason that it is located in these kinds of an inaccessible location. In most scenarios, components mounted in this sort of inaccessible spots are intended to endure the lifetime of the engine, but not in this problem. The timing chain in the N47 can fail any where from 40 to 100k miles, producing catastrophic motor damage as its components eliminate synchronization.

Prognosis – Symptoms of a Failing Timing Chain

The signs and symptoms of a unsuccessful timing chain commonly look steadily as the chain becomes extended and extra worn. As a consequence, you are not likely to detect a sudden spectacular symptom right until the chain is around to crack wholly. As an alternative, imagine about how your motor vehicle is executing nowadays and how it executed a lot of months in the past. Compact concerns could counsel that the chain is about to are unsuccessful entirely.

Right here are some of the signals that your timing chain is failing:

  • Rough idling: Commence your vehicle and walk absent. It is doable that the timing chain is donning out if it shakes or vibrates a lot more than normal. Of system, there are other difficulties that could end result in severe idling, but the situation is normally worth investigating because it tends to worsen in excess of time.
  • Unusual noises: You might hear your N47 motor rattle, specially when it is idling, but not only when it’s idling. The issue could be that the timing chain is loose and rattling against everything else if the audio is persistent and rough. 
  • Metallic shavings in the oil: Around time, the timing chain will don down. When it reaches the conclusion of its handy lifetime, it might emit metallic shavings. If it does, it will end up in your motor oil, possibly producing further challenges.  Nevertheless, any worn-out part of your motor vehicle can produce metal shavings, so it’s value on the lookout into before basically replacing the chain.
  • Engine failures: If your BMW would not begin, the chai may well be weakened and not supplying sufficient stress to start the motor. If the chain breaks whilst you are driving, it is possible that the timing chain has broken as very well. If this happens, the pistons might be broken, and the belt trouble may well lead to far more injury to your vehicle.
  • Engine misfires: Your N47 motor may well misfire ahead of the chain has absolutely snapped. The cam and the crankshaft are joined by a chain. The chain may well bring about the vehicle to skip a gear on both the crankshaft or the camshaft if it is overly stretched out. It will turn out to be much more stressed as a outcome of this, and it will ultimately crack.
  • Check out engine mild is on: Of course, the examine motor mild could sign a large variety of points have long gone incorrect with your BMW. Nevertheless, it’s possible that the timing chain has unsuccessful or is before long to fall short.

Replacement and Repairs

Due to the fact the timing chain is in these kinds of an inaccessible site, the mechanic will have to thoroughly take out the engine from its bay to obtain access to it. Using the engine out is a enormous and tough enterprise in and of by itself. Adhering to that, a further lengthy disassembly is required to achieve entry to the chains on their own.

3 timing chains are incorporated in the timing chain substitution kit: a person for the oil pump, 1 for the camshaft, and just one for the large-strain gasoline pump. You will also require the looking resource package to retain the crankshaft and camshaft synchronized when you’re operating on them. These are the primary tasks that need to be completed after eliminating the engine from the bay in purchase to exchange the timing chains.

To begin, make confident that cylinders 1 and 4 are at major useless centre in buy to keep the point for synchronizing the factors.

With the instruments you have, lock your crank shafts at this place.

Remove the camshaft chain tensioner to loosen the chain a minor, and loosen the three bolts on the camshaft sprocket.

It will be easier to clear away the fuel pump sprocket if the superior-stress gasoline pump is turned off.

Clear away the flywheel from the crankshaft by getting rid of the bolts that keep it in position.

Eliminate the starter motor’s bolts to acquire obtain to the oil sump.

By undoing the essential bolts, you can remove the oil sump.

Eliminate the timing cover by loosening the nuts that hold it in place. It will consider some prying and a few delicate taps with the hammer. You can now obtain all of the chains and sprockets.

By loosening the bolts, you could now take out the oil pump sprocket and the oil pump guides. Remove the oil pump’s chain as very well.

Similarly, remove the camshaft sprocket’s guides and tensioner, as properly as the sprocket and belt.

After TDC, twist the crankshaft 45 levels and take away the superior-tension fuel pump tensioner, guides, and sprockets. Get off the belt and the sprockets as very well.

The past item is your oil sprayer, which you may perhaps take out for replacement if necessary.

Then, in reverse purchase, put in the substitute belts, ensuring that all parts are in sync right up until the conclusion.

Conclusion

This timing chain difficulty is a design and style flaw in the motor, and the only technique to remedy it is to steer clear of automobiles with this N47 engine or, if attainable, get rid of it in working purchase. Because of the emission command gear place in it, these types of as the EGR and DPF, this engine also has a ton of challenges.







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