Introduction
From 2007 to roughly 2014, the BMW N47 was an inline 4-cylinder diesel engine that was used within the BMW 1, 2, 3, and 5 sequence, in addition to the X1 and X3 diesel fashions.
The N47 engine sequence is liable to early timing chain failure on account of extreme timing chain put on. The state of affairs is indicated by a rattling noise coming from the engine’s rear. Failure of the timing chain might necessitate engine substitute or a pricey restore. The issue impacts all purposes and energy variations of the engine manufactured between March 1, 2007 and March 1, 2011. Essentially the most severely broken items, which require probably the most substantial repairs, had been manufactured between the dates of 01.03.2007 and 05.01.2009. UPDATE – It seems that a small variety of engines made after the recall are having issues.
Timing chain
The timing chain on this engine is sandwiched between the engine and the transmission in the back of the engine. Its substitute is very troublesome as a result of it’s situated in such an inaccessible location. Usually, components put in in such inaccessible areas are meant to outlive the lifetime of the engine, however not on this state of affairs. The timing chain within the N47 can fail anyplace from 40 to 100k miles, inflicting catastrophic engine harm as its parts lose synchronization.
Analysis – Signs of a Failing Timing Chain
The signs of a failed timing chain often seem progressively because the chain turns into longer and extra worn. Because of this, you’re unlikely to detect a sudden dramatic symptom till the chain is close to to interrupt fully. As an alternative, take into consideration how your car is performing at present and the way it carried out many months in the past. Small points may recommend that the chain is about to fail fully.
Listed below are a few of the indicators that your timing chain is failing:
- Tough idling: Begin your vehicle and stroll away. It’s attainable that the timing chain is carrying out if it shakes or vibrates greater than normal. In fact, there are different points that might end in harsh idling, however the difficulty is all the time price investigating as a result of it tends to worsen over time.
- Unusual noises: You may hear your N47 engine rattle, particularly when it’s idling, however not solely when it’s idling. The difficulty could possibly be that the timing chain is free and rattling in opposition to the rest if the sound is persistent and tough.
- Steel shavings within the oil: Over time, the timing chain will put on down. When it reaches the top of its helpful life, it could emit steel shavings. If it does, it’s going to find yourself in your engine oil, maybe inflicting additional points. Nonetheless, any worn-out portion of your automobile can produce steel shavings, so it’s price wanting into earlier than merely changing the chain.
- Engine failures: In case your BMW wouldn’t begin, the chai could also be broken and never supplying sufficient stress to begin the engine. If the chain breaks whilst you’re driving, it’s attainable that the timing chain has damaged as nicely. If this happens, the pistons could also be damaged, and the belt downside might trigger extra harm to your automobile.
- Engine misfires: Your N47 engine might misfire earlier than the chain has fully snapped. The cam and the crankshaft are linked by a series. The chain may trigger the car to skip a gear on both the crankshaft or the camshaft whether it is overly stretched out. It would turn out to be extra pressured because of this, and it’ll finally break.
- Examine engine mild is on: In fact, the test engine mild may sign a big number of issues have gone mistaken together with your BMW. Nonetheless, it’s attainable that the timing chain has failed or is quickly to fail.
Alternative and Repairs
As a result of the timing chain is in such an inaccessible location, the mechanic should completely take away the engine from its bay to realize entry to it. Taking the engine out is an enormous and troublesome endeavor in and of itself. Following that, one other prolonged disassembly is required to realize entry to the chains themselves.
Three timing chains are included within the timing chain substitute package: one for the oil pump, one for the camshaft, and one for the high-pressure gasoline pump. You’ll additionally want the wanting software package to maintain the crankshaft and camshaft synchronized whilst you’re engaged on them. These are the first duties that have to be accomplished after eradicating the engine from the bay so as to change the timing chains.
To start, be sure that cylinders 1 and 4 are at prime lifeless heart so as to retain the purpose for synchronizing the factors.
With the instruments you’ve, lock your crank shafts at this location.
Take away the camshaft chain tensioner to loosen the chain slightly, and loosen the three bolts on the camshaft sprocket.
Will probably be simpler to take away the gasoline pump sprocket if the high-pressure gasoline pump is turned off.
Take away the flywheel from the crankshaft by eradicating the bolts that maintain it in place.
Take away the starter motor’s bolts to realize entry to the oil sump.
By undoing the required bolts, you possibly can take away the oil sump.
Take away the timing cowl by loosening the nuts that maintain it in place. It would take some prying and some gentle faucets with the hammer. Now you can entry the entire chains and sprockets.
By loosening the bolts, you could now take away the oil pump sprocket and the oil pump guides. Take away the oil pump’s chain as nicely.
Equally, take away the camshaft sprocket’s guides and tensioner, in addition to the sprocket and belt.
After TDC, twist the crankshaft 45 levels and take away the high-pressure gasoline pump tensioner, guides, and sprockets. Take off the belt and the sprockets as nicely.
The final merchandise is your oil sprayer, which you will take away for substitute if essential.
Then, in reverse order, set up the substitute belts, guaranteeing that every one parts are in sync till the conclusion.
Conclusion
This timing chain difficulty is a design flaw within the engine, and the one methodology to treatment it’s to keep away from automobiles with this N47 engine or, if attainable, eliminate it in working order. Due to the emission management gear put in it, such because the EGR and DPF, this engine additionally has plenty of points.
