E70 30d - Smoke from down by dpf

[MrSweet1991]

Hi All,

So I finally replaced the valve cover gasket along with the injectors seals that where leaking diesel onto the valve cover. I took it for a test drive and its smoking down from by the DPF, exactly the same as before, but as I never had any engine degreaser I didn't clean up the oil from before so I think (hope) it's just the residual oil, but how long should I expect it to continue for before taking another look just on the off chance there's another reason for it.

Here's a video of the valve cover removed and the oil residue from what appeared to have started from the back corner of the valve cover onto the manifold and further down.

https://youtu.be/VZz6-kEohIk

Here's some photos







And here's how it's smoking after replacing the valve cover

[wcs531]

I feel like the valve cover gasket is the only way oil can get up that high (at least that far back on the manifold), so im assuming this resolved itself once the oil burned off?

Im not sure what the single turbo setup looks like on the 30d but oil feed lines on the NA spec 35d turbos seem to be very common failure points. Not a bad idea to check turbo oil drain/return line also.

Other thing is the seals in the turbo itself, but I believe that would cause large amount of smoke from the exhaust.

[MrSweet1991]

Hi mate,

I've been working on the car ever since I got it (I knew it would need some work) but man it's taking long haha. So, Intake manifold gaskets replaced and swirl flaps blanked as they caused a huuuuge oil vapour leak onto that side of the engine.

Injectors and valve cover removed, valve cover new gasket and gasket sealent around the entire gasket (did this on my E90 and still holding good now) injectors had new copper, body and return line O-Rings replaced.

It seemed that maybe the smoke had "burned off" after going to the alignment shop, so I took it for a motorway run, exhaust hit 600 degrees doing a regen and no smoke! Booked an alignment in and on that day I did a small trip around town and omd it was smoking again.

Upto now I believe the issue is with injector 6, I took a video this morning and it seems to be leaking from the fuel return line.. But why! It has a new O-ring and from my rough inspection I couldn't see any cracks..

I don't know why slo-mo is so strange to see on anything other than my phone but look at the opening of the white collar on the return line, its running down pretty fast.

The only thing I can think of right now is hooking up a see through hose to the return line nipple on the injector with a bottle on the end (pretty much a leak back test) except I'm ruling out the return line hose being faulty or the injector nipple having a hairline crack (I hope not)

If all is well I may take the return line off my E90 because BMW want £135 and my E90 has 180k on and the return line is fine so it doesn't seem to me like something that's prone to failing, maybe somebody leaned on it once and broke something on the T-connection.

[wcs531]

My guess would definitely be the return line, just because I feel like if the nipple on the fuel injector cracked it would be at the base.

Id thoroughly inspect the plastic on both pieces one more time before pulling the return line off of your 330d.

Another possible idea - they do make UV dyes for diesel that may be worth a shot? It would get all over the place obviously but once you wipe off the excess (not sure how easy it is to wipe off though) the crack may retain some UV dye that could be visible with a cheap uv flashlight

[wcs531]

Just realized one more thing. The return line fittings are just held on to the rubber hose with ear clamps. Don't see why you couldn't cut the ear clamp and swap just one fitting, using small hose clamps to replace the ear clamps.

Maybe a little thread locker on the hose clamp screw once you're finished testing, just in case since it would be permanent.

[MrSweet1991]

Good idea, so dremel the existing clamp off both and use a hose clamp to secure the hose back on again. I could probably take the hose clamp off the vacuum hose on the E90 as well. I'll give that a go tomorrow, thinking about it, is there another way to get the clamp off both without sparks haha..?

[wcs531]

Diagonal cutters or end cutters should work, not sure if you have different names for them over there.

Also its pretty hard to ignite diesel. If you do dremel it id still be very careful and not direct a bunch of sparks directly onto it but I do think it would take more than a few sparks from a dremel to ignite it.

Either way just be careful not to break any of the other return line fittings or worse the injector nipples.

[MrSweet1991]

Originally Posted by wcs531

Diagonal cutters or end cutters should work, not sure if you have different names for them over there.

Also its pretty hard to ignite diesel. If you do dremel it id still be very careful and not direct a bunch of sparks directly onto it but I do think it would take more than a few sparks from a dremel to ignite it.

Either way just be careful not to break any of the other return line fittings or worse the injector nipples.

Yes I know what you mean, with your last post pointing out that they're called ear clamps I searched and seen how they can be removed with those cutters, annoyingly I don't have a pair I don't think but I'll figure something out. I'll do it first thing tomorrow as I need the car sorted. I've had it about 4 weeks and drove it maybe 3 days

Still got a wheel alignment and transmission to do yet once the smoking is sorted.

Update:

Well that didn't go to plan, the mini snips couldn't cut the ear clamp off so I actually drilled through the small opening and as it popped open it snapped the drill bit and flung haha. Anyway, clamp off so I tried twisting and pulling but the plastic nipple inside the hose was so small it snapped. I'd put this more down to the E90 being on 180k but those return line hoses are seriously thick, the inside hole is tiny so in my opinion removing the T clip or what ever it's called is very slim.

I'll have to put my little leak back contraption on the injector return nipple and see if it leaks. If not, the injector nipple is of course fine and just be the return hose in which case I Jay just buy one off BMW.

[wcs531]

oh no, sorry about that. I would not have imagined that could happen. BMW must be designing the plastic to disintegrate after a number of years for recurring revenue.

[MrSweet1991]

Originally Posted by wcs531

oh no, sorry about that. I would not have imagined that could happen. BMW must be designing the plastic to disintegrate after a number of years for recurring revenue.

Nothing to be sorry about, it was a good idea and I've seen on another thread somebody do the same thing, I suppose it's just luck and at least it snapped off the E90 which is off the road and just being used for parts if need be.

[MrSweet1991]

Right, the diesel leak is sorted. Took it out for a drive and fine, then took it on a dual carriageway, came back and seen this

https://youtu.be/icWHtdY8dpg

Legit confused now, valve cover has been done and from what I can see with the endoscope it's absolutely fine (from the areas I can inspect anyway)

There does appear to be oil around the head gasket, I do believe this is common to see after having a failed valve cover gasket as the head gasket has a lip.. But yeah because of the tiny amount of space I have and the heat in that area I'm struggling to source where exactly its coming from.

View post on imgur.com

View post on imgur.com

[wcs531]

I would look at everything turbo related:
Oil Feed line
Oil Return Line
Seals in the turbo itself

While this video is related to the head gasket, it shows that oil can drip down the outside of the downpipe from the turbo