Well that was not fun . . .

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I got a call that the parts arrived and they have the transmission/motor and REx down . . .
motor_200.jpg

Here we see the rest of the bolt in the transmission/motor mount. You can clearly see there was a rocking motion that just like a coat hanger wire, flexed and broke the bolt.

The new mount frame is substantially larger, a solid aluminum piece:
motor_210.jpg

Notice the "U" shaped channel so instead of putting all the stress on the bolt, the shoulders of the "U" will transmit the forces to a much larger area.

Here are the two new bolts and the remaining bolt from the engine side:
motor_220.jpg

Substantially larger, the new bolts will be substantially stronger. If I remember correctly, the strength increases by the the square of the diameter.

The original bolt had a smooth shoulder which would minimize the stress on the bolt head:
motor_230.jpg

However, the stresses deformed the bolt attachment piece enough to lead to vibration and fracture in the threaded part, narrowest part of the bolt. In contrast, the new bolt is substantially larger and threaded the whole length.

There is a new mount piece on the engine side:
motor_240.jpg

Again, substantially larger piece with the "U" shaped shoulders to take up the stress. It has to be "U" shaped as the engine is raised to fit into the body/frame pieces.

The part that came from Germany was the air conditioner (AC) hose:
motor_250.jpg

When the mount failed, everything dropped and the refrigerant hose broke . . . and leaked it out. So part of the repair, after the hose replacement, is to draw a vacuum and recharge the AC. Had the repair been done under a recall, the refrigerant leak would not have happened and replacement hose would not have been needed.

From the rear, here is the transmission/motor assembly and REx:
motor_260.jpg

Draped in the foreground is the cabling to the tail lights. I have a 2" receiver hitch but it has no lights. To add lights, I'll need a 12V power, 'relay' box that amplifies the light signals to generate the typically much higher drawing trailer lights.

Finally, here is a neat shot of the 5-point attachment holding the wheels:
motor_270.jpg

Truly brilliant, these five, links with rubberized bushings hold the wheels semi-rigid and aligned. Yes, there will be small displacements from bumps and normal operation but the 5-points bring the wheels back into alignment.

Final repairs and assembly are in progress and I told the tech,"Take your time and do it right. I have my Prius which is working perfectly fine."

On the way out, I suggested the service writers and staff take a minute or two to see what the repairs look like. I got the impression this is the first one in this area.

Bob Wilson
 
bwilson4web said:
The new mount frame is substantially larger, a solid aluminum piece:

bwilson4web said:
There is a new mount piece on the engine side:

I believe that your i3 had already had the motor mount bolt replaced under a service bulletin as have many early i3's. In your case, the new bolt was insufficient, so new stronger mounting pieces and bolts were installed. Meanwhile, the rest of us are still driving around with motor mounts and bolts that are insufficient and subject to breaking which would be a very expensive repair outside of the warranty.

Bob, do your discussions with your BMW service department suggest that all early i3's will have their insufficient motor mounts and bolts replaced at no cost to the owner? I assume that all later i3's include these stronger motor mounts and bolts.
 
alohart said:
. . .
I believe that your i3 had already had the motor mount bolt replaced under a service bulletin as have many early i3's. In your case, the new bolt was insufficient, so new stronger mounting pieces and bolts were installed. Meanwhile, the rest of us are still driving around with motor mounts and bolts that are insufficient and subject to breaking which would be a very expensive repair outside of the warranty.

Bob, do your discussions with your BMW service department suggest that all early i3's will have their insufficient motor mounts and bolts replaced at no cost to the owner? I assume that all later i3's include these stronger motor mounts and bolts.
I can not say about the earlier versions as I got the car the last week of May 2016. I can only report what I've seen.

I'm just pleased the service department has let me in the shop to see the parts and talk with the techs. I know other dealers treat their repair shop as a secret and discourage discussions with their tech staff. The local Toyota shop really wants all conversations via the 'service writer' and they are just glorified clerks.

I'm submitting my NHTSA report tonight with the URL for this thread. I'll send a copy to BMW USA as a curtesy. I'm not doing this to be mean but I was lucky: (1) I know how to deal with problems, and (2) in a relatively good place to roll off the road into a parking lot and space. Had it been my wife or folks who are a little more excitable and less technical ... <UH OH!>

Thinking about the problem, I have the following thoughts:

  • Non-destruct survey of all motor mount bolts - At a minimum, the cars should be brought in and have the bolt inspected. There are non-destruct inspections that can probably detect the early fractures. The alternative is to support the car and replace the bolt which is sent off for dye testing. Cars showing the early problem are scheduled for a full replacement.
  • Train the connect team on towing options - the car should have been towed Friday evening to the shop, not wait until Saturday when I made the arrangements.
  • Develop a workaround to put the car in "N" - at a minimum, two, color coded cables that can be reached from the bottom of the car that will unlock the parking paw. Using a jumper cable, an external 12 V source should be able to put the car in "N". NOTE: it isn't clear that had it been in "N", the car could have been put on a flat-bed without further damage for risk. This workaround should be signed off by BMW engineering!

Having gone through this experience, I would consider taking a BMW i3, especially the BMW i3-REx, into the shop and ask them to replace the motor mount bolts and give you the old one. There would be a part and labor cost. Then send the old bolt to a shop that can do a dye and/or fracture test. IF the report comes back, report the results to the Service department and ask for a warranty repair of the motor mounts. If you are coming up on the end of warranty, it becomes more important to have it done ... soon.

If you get any push-back, find an independent shop and arrange for the replacement and testing.

Bob Wilson
 
I got a nice e-mail note from "[email protected]". They gave me a number to call and even though it is Friday before Christmas Holiday weekend, I'll give a call and see if there is a better time and day to talk with the team. The key is letting them know I understand 'stuff happens' and I am not pissed. Just there may be a few things that could be handled a little better. Things that might reduce future costs and avoid customer angst.

I won't share the e-mail and will only paraphrase the conversations. But this is how professionals work. <GRINS>

Bob Wilson
 
Well I checked and my PDF report was not at the NHTSA site. I tried again but got a web error. So I filled out the web form and generated complaint, "10938956". Hopefully the NHTSA got it this time.

I did see one early report that reads like a broken motor mount bolt but only by the symptoms. Regardless, best to share a problem . . . not to be mean but keep everyone on the same page. Secrets help no one and I've already forward the PDF form to BMW USA.

Bob Wilson
 
Bob,

I am considering a 2014. I would be grateful if you can post pictures of what these new U shaped shoulders look like from the top and where they are located, if the tray under the boot cover is opened. I would like to make sure this fortifying fix is already in place in an out-of-warranty vehicle.

Many thanks.
 
Srivenkat said:
I would be grateful if you can post pictures of what these new U shaped shoulders look like from the top and where they are located, if the tray under the boot cover is opened. I would like to make sure this fortifying fix is already in place in an out-of-warranty vehicle.
My sense is that a very low percentage of early i3's have had the improved motor mounts installed because very few motor mount replacements have been reported by the many i3 owners in the Facebook i3 group and in this forum. This would be an expensive update for BMW, so they haven't typically approved this update unless an i3 has broken the motor mount bolt that was installed during the BMW motor mount bolt service campaign. If true, you'll be extremely lucky to find a 2014 i3 with updated motor mounts.
 
Thanks. Does anyone know if the improved mount became a standard with 2016 or 2017 and later models? I see Bob had the repair done in Dec 2016.
 
Srivenkat said:
Does anyone know if the improved mount became a standard with 2016 or 2017 and later models?
I believe that owners of 2016 and later models have reported their motor mounts being the improved version. Maybe even some 2015's have the improved version. With the cargo area floor access panel removed, the improved aluminum motor mount is visually distinguishable from the black plastic version.
 
It's possible, but not necessarily certain that those units that just had the new bolt and later failed, had already been slightly damaged or overstressed, and it wasn't obvious. So, depending on the state of the original mount, if it was intact, the stronger bolt may be more than sufficient for the rest of the life of the vehicle. Keep in mind that the original prototypes had accumulated many hundreds of thousand miles and not exhibited any problems with the original design. It may be partly in that the roads in Germany tend to be in better repair than those in some other places, notably, the USA (there's a reason why they have expensive fuel costs...and it's not because the raw fuel costs that much more...it's the taxes they use to keep the infrastructure intact).

Anyway, my very early 2014 US model (made in APril 2014) is still okay, and I hope it stays that way. I understand, no guarantees, but personally, I don't worry about it. If you're really risk averse, consider a later model with the redesigned mount in it. I don't remember exactly when that production change occurred. You might be able to figure it out on www.realoem.com and look at the diagrams based on build date if someone doesn't remember exactly.
 
Thanks, Art and Jim. If I understand realoem right, it looks like the new mount became standard from 11/28/2015?

http://www.realoem.com/bmw/enUS/partxref?id=1Z43-USA-06-2014-I01-BMW_i-i3_60Ah_Rex&mg=22&sg=05&diagId=22_0203&q=22116878935
 
I am seriously looking at 2014/2015 models but still am nervous about the mount issue. Has anyone gotten the mounts replaced preemptively? If so, what was the cost. If it's not more than $1000, I might figure that into the cost of a 2014/2015 and get it done. Thanks in advance.
 
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