[natesi]

Originally Posted by F30ed

Let's look at facts:
1. Did anyone actually reported timing chain ripped? - Not that I remember.
2. When timing chain breaks some valve would drop into piston work area making spectacular *BANG!!*. Did anyone reported that explosion? - NO. This means at the time of failure timing chain is in working condition.
3. So what is reported? "Oil pressure loss" is reported. Why? Either oil chain rips, or oil pump breaks.

I doubt that N20 problems are related to timing chain. Maximum it may make noise when plastic cassette is broken.

Excellent points.

[KGB_123_99]

Originally Posted by F30ed

Let's look at facts:
1. Did anyone actually reported timing chain ripped? - Not that I remember.
2. When timing chain breaks some valve would drop into piston work area making spectacular *BANG!!*. Did anyone reported that explosion? - NO. This means at the time of failure timing chain is in working condition.
3. So what is reported? "Oil pressure loss" is reported. Why? Either oil chain rips, or oil pump breaks.


I doubt that N20 problems are related to timing chain. Maximum it may make noise when plastic cassette is broken.

I think what happens is the timing chain guides break and then the broken piece jams the oil pump chain.

[motorwerkeman]

If you look into the part revisions:

-01/15 Timing chain revised
-04/15 Oil chain revised

My key question in all of this is: Have we seen this type of failure in cars built after 01/2015? After 04/2015?

I think what happens is the timing chain guides break and then the broken piece jams the oil pump chain.

I think the stretched chain causes stress on the guides which in turn causes them to break. The part numbers for the slide rail and guide seem to be the same since production began.

[OUGrad05]

N20 with 40k miles, looks ok to me, a little bit of scuffing on the chain but nothing that looks to compromise the integrity of the chain.

We're selling/trading it anyway, we've gotta get a bigger vehicle

[Gamb1t]

The scuffing means it is rubbing against something.... Possibly the plastic guide? Whatever it is rubbing against that part too is being frictioned off. And if it is the plastic guide then it's a matter of time before the plastic guide's structural integrity becomes compromised and shatter.

Drawing upon my bike maintenance days, stretched chains are normally due to worn sprockets. The teeth would look like shark's fins. Unless one is putting down major torque gears/sprockets last a long long time.

Would be good to know the driving habits of the drivers with this issue.

[OUGrad05]

Originally Posted by Gamb1t

The scuffing means it is rubbing against something.... Possibly the plastic guide? Whatever it is rubbing against that part too is being frictioned off. And if it is the plastic guide then it's a matter of time before the plastic guide's structural integrity becomes compromised and shatter.

Drawing upon my bike maintenance days, stretched chains are normally due to worn sprockets. The teeth would look like shark's fins. Unless one is putting down major torque gears/sprockets last a long long time.

Would be good to know the driving habits of the drivers with this issue.

This is the new design so if that's the case everyone with an n20 is screwed and frankly I don't believe that. Your rationale is reasonable but you are also assuming in the redesign phase of the parts they haven't accounted for this. Also a few wear marks doesn't necessarily mean that the wear is going to eventually cause a failure....but I suppose it could.

[etinifni]

Had my timing chain/guide replaced by BMW a few months ago, approximately 7k miles ago. Here is a pic I snapped this morning.

[IMG]http://d.pr/i/2WZ2+[/IMG]

[Gamb1t]

Originally Posted by etinifni

Had my timing chain/guide replaced by BMW a few months ago, approximately 7k miles ago. Here is a pic I snapped this morning.

[IMG]http://d.pr/i/2WZ2+[/IMG]

Can you share how you got BMW to replace the chain? Symptoms?
Out did it break which might let to catastrophic engine issues.

[etinifni]

Originally Posted by Gamb1t

Can you share how you got BMW to replace the chain? Symptoms?
Out did it break which might let to catastrophic engine issues.

I explained my situation in the beginning of this thread. It would probably be easier just to go back and read it. I'm currently on mobile so it looks like I posted it on page 6 & 7.

Also posted here:

2012 BMW N20 Engine Failure!!! http://f30.bimmerpost.com/forums/sho....php?t=1256248

[cheychey]

Anyone can pm me the email for those who are in charge at bmwna that can help with my situation. I have a 2012 bmw x1 28i with 100,600km that I recently bought from a used car dealership in mississauga ontario in dec 2016. They had in turn bought the vehicle from parkview bmw toronto in sep or oct 2016. The vehicle was on a lease till aug 11th 2016. Service history shows it was maintained and serviced up to date. I recently heard a slight whining sound on acceleration and took in to bmw etobicoke for diagnoses. They notified me that the timing chain and oil pump chain needs replacing due to excessive wear on the chains and sprockets causing the whining noise. Another issue is that the turbocharger oil feed line needs replacing as well. Both issues I have read about have been common issue of the n20 engine especially the timing and oil pump chain wear. I want bmw to atleast cover that repair. Anyways if anyone can pm me the contacts i would need to send my concern to then. will not threaten them yet I will give them a chance first.

[Gamb1t]

Why don't you work directly through your BMW dealership? Btw it's BMW Canada you would be dealing with. All the best and please update us.

[Billfitz]

Originally Posted by cheychey

have a 2012 bmw x1 28i with 100,600km that I recently bought from a used car dealership in mississauga ontario in dec 2016. They had in turn bought the vehicle from parkview bmw toronto in sep or oct 2016. The vehicle was on a lease till aug 11th 2016.

Not that it helps the OP, but this is why you only buy CPO. The reason why the leasing dealer wholesaled the car off to a used car dealer is because he examined the car and knew it had issues that he didn't want to deal with.
OP, go to the leasing dealer, and contact BMW Canada. Between the two of them you might come to an arrangement.

[F30ed]

Originally Posted by etinifni

Here is a pic I snapped this morning.
[IMG]http://d.pr/i/2WZ2+[/IMG]

The picture is blurry, but overall looks ok. Can you tell in words what is wrong there?

[etinifni]

Originally Posted by F30ed

The picture is blurry, but overall looks ok. Can you tell in words what is wrong there?

Not sure what you mean, I was just posting a picture of how my chain looks post upgrade. Is there something wrong?

[Billfitz]

Nothing wrong, but it does show that the plastic guide doesn't stay white, it turns brown after exposure to oil. Earlier pictures of a removed old chain and an unused new chain would give the impression that if you've got a brown plastic guide that you have the old version, and that's not the case.

[BlueCrabMafia]

Originally Posted by cheychey

Another issue is that the turbocharger oil feed line needs replacing as well.

Your turbo oil line should be covered under a recall, at least in the US it is. I just had mine replaced via recall.

[davitd]

Originally Posted by Billfitz

Nothing wrong, but it does show that the plastic guide doesn't stay white, it turns brown after exposure to oil. Earlier pictures of a removed old chain and an unused new chain would give the impression that if you've got a brown plastic guide that you have the old version, and that's not the case.

There is no revision to chain guides or oil pump. Only oil pump chain and timing chain have been updated. If one has the old version of the oil pump chain, I would definitely update it since the new design seems to be more robust. Otherwise I would not bother with a slight whine and would not rush to replace bunch of parts worth more than USD2 k. From my experience the whine is more associated with balance shafts or oil pump but the design of these parts has not been updated and thus there is no guarantee that the whine won't be back.

P.S. timing chain guide failure leads to higher pitched whine that needs to be addressed immediately. There are numerous videos on the web of this sound and one can not miss it.e.g. visit bmwtechnician's blog.

[Billfitz]

Originally Posted by davitd

There is no revision to chain guides

You missed my point. This picture shows old versus new oil chain:


The new unused guide is white, because it hasn't been exposed to oil yet. Some have made the mistaken assumption that the new chain will have a white guide. Before installed, yes, but after installed, no.

However, there is a visible difference between the two. The links of the old version are all made with two plates back to back. In the new version the center links are still two piece, but the inboard and outboard links are one piece. Whether that's significant or not I can't say.

[BlueCrabMafia]

Originally Posted by Billfitz

You missed my point. This picture shows old versus new oil chain:
[img]http://f30.bimmerpost.com/forums/att...1&d=1482370445[/img]

However, there is a visible difference between the two. The links of the old version are all made with two plates back to back. In the new version the center links are still two piece, but the inboard and outboard links are one piece. Whether that's significant or not I can't say.

I would say the chain links being one piece in the inboard and outboard of the chain is a significant update. Thicker one piece material probably prevents the chain from stretching as it did with the 2 piece design.

[KGB_123_99]

Still in shock that a company whose middle name is Motor has such a "teething" problem with chains you would normally expect from a brand new car maker.

Amateur hour...

[jcbkrmr]

Finally, after 8(8!) weeks of being on a lift at the dealership my X3 has been repaired under warranty and returned to me. As glad as this has made me and my wife, there are still some things to be concerned about.

First, the replacement engine was selected by the dealership, this did not go over very well with the warranty company who were able to find a much cheaper replacement... this is all well and good, except the replacement that was installed still has the out of date secondary chain inside of it. I went back and forth with the dealership and BMWNA for multiple days about getting the chain updated. The best they could do was quote me $2400 for the replacement. I balked at this proposition and happily accepted the 12mo. warranty extension that they offered on the replacement engine. I did this assuming that there will either be a recall between now and then or in the worst case I would get the new chain installed by an independent mechanic the day before the warranty expires.

Second, on our way home from picking up the car there was a very noticeable vibration through the seats and arm rests (briefly through the steering wheel while accelerating at low speed). The vibration has a frequency that seems to vary with rpm at nearly every speed. I am currently trying to identify the frequencies as a function rpm using some rudimentary vibration analysis tools. This vibration was accompanied with some very strange noises (something like a whine combined with a lugging sound) coming from the engine bay. We notified the dealership of this and they told us to "keep an eye on it". I guess they are hoping that it "just goes away", in my experience that never works. I initially second guessed myself, thinking that it could be normal, however, we had just been driving a loaner '17 X3 and it was smooth as butter and super quiet once up to operating temp. In fact, the vibration from the "new" engine feels worse than the old engine did immediately prior to the failure of the secondary chain. I am thinking that the secondary chain in this engine has already been stretched, causing the counterbalance shafts to be "out of time" with the engine.

Unfortunately, I think I am going to have to bring the car back to the dealership and tell them that I am not satisfied with the work done on the vehicle and they need to have another crack at it. But I am not sure how all of this will play out with regard to the burden of the warranty be fulfilled, etc. etc. If anyone has ideas as to the source of these vibrations, and/or what course of action I should/can take to get this thing running properly I would greatly appreciate it!

[natesi]

Wow; what a nightmare.