My car’s engine burns a lot of oil

We often get the question why is my car burning so much oil? The answer lies in the details, for instance we have here 3 different pistons from 3 different era. They are about a decade apart from each other. Take a close look at the oil rings on the pistons. The first one is the thickest at 3.98 mm, this one is the oldest piston. The next at the middle from a MINI, it is a little thinner.  The last one is the dirty looking one, which is covered in carbon at 1.98 mm and appears to be super thin.

BMW pistonsInternal Combustion Engine Pistons

That dirty looking piston with the super thin piston rings on it  from a 2013 BMW 328xi with the N20 engine. Why is it so thin you may ask?

The #1 reason  is to reduce friction and increase the fuel economy which has been legislated and called the CAFE (Corporate Average Fuel Economy in short CAFE). The manufacturers must comply with a mandated fuel economy which is for stage 1 we already passed in 2016 and the next stage is set for 2025. Today ICE (internal combustion engines in short) must leave up to strict fuel and emission standards, doing so the manufacturers are looking to maximize the ICE fuel economy by the means of minimizing the energy required to move the internal components.

This a phenomenon on all late model modern engines, so what can be done about it?

You as a consumer must stay on top of things for instance follow a schedule for your oil service based on your driving habits. Choose a knowledgeable service facility to help you reduce your engines oil consumption by using the best possible high tech motor oil for the application, this should be determined by experience not by convenience.

You also need to remember, to make your engine last, you must have it running at least half an hour to 45 minutes to be able to get the oil circulation heat up and perform a self clean internally. The low tension skinny piston rings will allow more water to condense into the motor oil, which will be accelerating the internal engine wear prematurely.

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How does it work? This is the chemistry, which makes your engine tick HC, (hydrocarbon) fuel when burns in the combustion chamber with O/2 (oxygen). It will create a by product H2O (water) that water or steam is visible in cold start say in -10C or bellow. That steam or water vapour is always present at all the time so some will pass by the skinny rings and will condense into the motor oil.

This has 2 effects, one it will dilute the motor oil, 2 it will sink to the bottom of the oil pan if the engine runs extremely short distances. This acidic water will sink to the bottom of the oil sump and at next cold start the engine will get water pumped to it’s internal components instead of motor oil, as we all know water is a terrible lubricant. The only solution, especially on the German vehicles, the operator, driver must heat up the oil extensively so the crankcase ventilation system can handle the excess water which gets vaporized and get send back into the engine combustion chamber and will be expelled in the process.

So in short as the saying goes, if you don’t use it, you will loose it. Perhaps should rephrase it, if you don’t use it long enough you may loose it a lot earlier stage than you should be, is the ultimate motto for this.

Any questions how may we help? Give us a call to: 905.795.0419!

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Recommended synthetics motor oils for BMW

The Famous N20 Engine Timing Chain Issue

The weakest link on the BMW N20 engine is a common timing chain failure, due to the guides breaking from the chain oscillations. The timing chain in most cases will rattle, oscillate wildly and in the process will break pieces off the chain guide, which will get picked up or sucked up by the oil pump which destroys the engine suddenly in the process.

The broken guide pieces may block the entire pick up screen for the engine oil pump which will seize or destroy the engine components, due to sudden lack of lubrication.

The real cause in my opinion is the ECO mode which is the default mode in the transmission after every single start of the vehicle. The chain oscillations are caused by the transmission selecting the highest possible gear with the lowest possible engine rpm to maximize the efficiency of the engine as it has been mandated by the CAFE (corporate average fuel economy in short). We had the first stage of the CAFE mandated for 2016 the next stage is proposed for 2025. The real issue at hand unfortunately is the 8 speed automatic transmission, which is programmed to provide the best possible gas mileage, which in this case is counterproductive as it will lag the engine at very low rpm to minimize fuel consumption and to maximize the efficiency of the engine.

BMW N20 engine repair because of timing chain failure.

BMW N20 engine repair

The N20 will fire at every half turn which is 180- degrees this will (two full turns equates to 720 degrees for all the 4 cylinders to be fired) which is problematic for the single row timing chain. I can tell you from the past, the last generation 4 cylinder sold in this part of the world was the M44 (before was the M42) which had a dual row chain to prevent this issue to happen.  So why did they switch to a single row timing chain system you may ask?

This is all done to maximize efficiency and to reduce the internal drag of the engine and it’s components.   Back then there was no CAFE standards, manufacturers were left to build whatever they deemed fit for the purpose.

This cars are equipped with a standard transmission in Germany, so they will get a work out when they are driven to the Autobahn. In North America every one of these cars are equipped with an 8 speed automatic transmission.

How can you prevent this problem? We recommend to flip your selector to sport mode after start and don’t be afraid to give your engine a work out, after all it was built for the Autobahn.  You can switch back to ECO mode to reduce the fuel consumption, when you drive on the highway at higher speed.

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This cars are meant to be driven spiritedly on the Autobahn. This doesn’t mean you have to drive it all the time as a maniac, it means keep the rpm at least medium or higher much as you can.  Naturally always use proper oil and filter, at more frequent intervals, than recommended by the manufacturer. You won’t believe how many inferior oil filters we find and replace on this cars where they got some cheap inferior filters installed elsewhere.

In case you are interested in a ECO car you may want to consider an i3 or other hybrids, perhaps a hybrid BMW and or a Prius.

You also should have your vehicle serviced by a specialist, a BMW technician, so we can give you an early warning which may prevent permanent engine damage. There are tell-tale signs of this issue for a trained seasoned BMW technician, this is what we are good at. We’re working on European cars since 1976.

Any questions, how may we help? Give us a call to: 905.795.0419!

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A perfect example of a BMW N20 engine failure because of timing chain issue.

 

BMW N20 engine failure

Here is a perfect example of a BMW N20 engine failure because of the lack of maintenance.

You can see on the third image, a bunch of granulated pieces and metal shavings, which resulted in a broken timing chain guides and chain failure. If you want to prevent this from happening, change your oil at minimum once a year or ten thousand kilometers.

Also try to forget about the ECO mode put your gear selector into sport mode and leave it in there.

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If you need any further information I will be happy to explain in person, how may we help? Give us a call to: (1) 905.795.0419!

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BMW Timing Chain Replacement