EGR Cooler tightening procedure by BMW

[ninja_zx11]

Found this while going through repair procedures in rheingold and thought it might be useful for someone.

You can see the special tightening sequence in the end of the document.

[ZetaTre]

EXCELLENT!!!!!!!! That's what I've been looking for.

I read that in some cases people have experience fracture of the EGR right around where the flange is, by the exhaust manifold.

Some blamed the new bracket added under the throttle valve on the opposite side. It makes absolutely no sense to me and I blame improper assembly by the technician that doesn't follow the sequence resulting in the cooler being misaligned. I just couldn't find the sequence but I remember reading about it: it makes perfect sense.

In summary, follow that sequence and you'll be fine. Don't torque 3, 4, 5 until the bolts on the flange and the clamp are torqued to specs.

[sgrice]

Thanks for this. I edited my post on thermostat-fan-egr cooler diy guide (link is here) to include a reference to this posting.

Best regards.

[ninja_zx11]

Great!!!

[JGard]

Well, for whatever it's worth, I used this guide when reassembling everything after doing my thermostat. That was about 1,000-1,500 miles ago and as of this morning, I believe there is a fairly major leak. I can hear exhaust spitting sounds when on the throttle, and I can smell it in the cabin as well. Engine malfunction light came on stating reduced power.

Looks like yet another service appointment for me. :| This makes 4 trips to the dealer since I bought my X5 back in February. Not a good record thus far.

[sgrice]

So sorry to hear this. There are certainly a number of references to cracked EGR coolers on the forums. I assume you saw the discussion between ZetaTre/Lpcapial and Bawareca debating the usefulness of the bracket that BMW added to the EGR cooler via a service bulletin.

Hope it gets fixed quickly - sounds like you've had enough issues to last for the next couple of years.

Regards.

[JGard]

Yeah, I'm kind of hoping here that it's just all original stuff in my car and this will be fixed from the service bulletin. I kind of fear them coming back and telling me I screwed something up and caused this. Of course, they don't need to know I replaced the thermostat, either.

But I do have the extended warranty, so either way I'd like to think I'll be covered.

[ZetaTre]

Let us know where it cracked! Also, did you have the bracket mounted?

[JGard]

I'll get a look in there tomorrow morning and hopefully grab a pic if I can fit any sort of camera in there. As for the bracket, which one? I didn't see anything aside from the cooler itself, so I assume no. There are the five bolts for it, two brackets on the cooler body itself, the two at the flange, and the weird one up on the other side of the cooler (cold side)

[ZetaTre]

Originally Posted by JGard

I'll get a look in there tomorrow morning and hopefully grab a pic if I can fit any sort of camera in there. As for the bracket, which one? I didn't see anything aside from the cooler itself, so I assume no. There are the five bolts for it, two brackets on the cooler body itself, the two at the flange, and the weird one up on the other side of the cooler (cold side)

There has been a service bulletin to retrofit a bracket that makes the assembly more rigid around the intake area (cold side). This reduces the risk of leaks at the flex joint.

You can take a look at it here -> https://drive.google.com/file/d/1mDX...ew?usp=sharing

You'd get a free cooler if yours is broken.

HOWEVER, note that like Bawareca has described, cracks at the accordion on the hot side have occurred afterwards. My theory is that is the result of improper tightening sequence by the technician who replace the cooler and not a result of the new bracket itself. A crack there is is more problematic because you have hot exhaust gasses over the thermostat and the result is the melting of the thermostat with consequent loss of coolant.

My recommendation to you would be to:
1) verify that you don't have said bracket in which case bring it over to the dealer, sit back and enjoy their cookies and java. Bring the bulletin along.
2) even if you have that bracket take the tightening sequence to the dealer and ensure you tell the SA to let the tech know to be particularly careful and follow the procedure.