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nike001
09-25-2011, 06:07 PM
Okay, I was going to post this in either the headlines thread or the what'd you do for your zhp today thread but I figured this deserves its own thread.

So, Terra and one of my mechanic buddies helped me do my VANOS today. Pulled my plugs and they were all black from burnt oil and the plugs from #3 and #4 were soaked in oil (esp #4)

The kicker is: CCV just replaced, No oil in coolant & no coolant in oil. Every plug was coated in burnt oil.

I need ideas from my ZHP brothers!! I can't continue to put oil every 1,000 miles in my car!

Hornung418
09-25-2011, 06:13 PM
Change your VCG and related grommets. Make sure you torque every bolt down to 11 lb-ft and in a criss-cross fashion starting from the front corner to the opposite back corner and work your way to the middle.

nike001
09-25-2011, 06:17 PM
VCG was replaced last november or so by the dealer... we re-used it after VANOS since nothing was wrong with it and did criss-cross putting it back on.

even still: I don't see how the VCG would have anything to do with my car physically burning oil

nike001
09-25-2011, 06:21 PM
The only good news of today: My shiz is squeaky clean!
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/263d007c.jpg

zj96sc
09-25-2011, 06:25 PM
How many miles? Engine mx history/oil change frequency/type of oil used? Compression numbers? General performance?

Maybe bad valve seals, maybe bad rings. Either way, a bunch of oil in your cylinders is never caused by something easy.

Hornung418
09-25-2011, 06:28 PM
Those center gaskets could be letting oil down into the Combustion Chamber. IDK, it's a small price to pay to know that it's done properly by you. Then you could definitely eliminate that as an issue.

Also you may want to pull the skid plate and make sure your Oil Pan is properly torqued to spec. You may be losing oil from a leaking seal.

nike001
09-25-2011, 06:29 PM
112k miles. Easily one of the cleanest zhp's on the road. The BMW techs love my car for how all the internals are literally almost brand new.

Oil: changed 2x since I've had it (13k mi).. one time with M1 0w40 and second time with Castrol 0w30(from terra's request)
You can see from my above pic.. that oil was changed in good intervals. My engine is one of the cleanest that I've seen...and I'm greatly appreciative of PO

Performance: I can pull on other zhp's I have messed around with and car doesn't miss a beat.

Should a compression test be my next course of action? We already have valve seals and rings on the possible suspects. I'm not really to accept one of those as the symtoms. That would be WAY too much money for me to do.

Hornung418
09-25-2011, 06:32 PM
Well that's the next step if you can't solve it with the basic troubleshooting.

nike001
09-25-2011, 06:36 PM
Well that's the next step if you can't solve it with the basic troubleshooting.

Haha I know. My buddy offered to help me do it and pull the engine to re-do everything in there. But that would be waaay too much $$.

Compression test next? Yay/nay?

Hornung418
09-25-2011, 06:45 PM
Yay.

Johnmadd
09-25-2011, 07:05 PM
[QUOTE=Hornung418;106293]Change your VCG and related gr[/QUOTE/]

+1

zj96sc
09-26-2011, 05:00 AM
Unless I seriously misunderstand the architecture of the M54, bad grommets or VCG aren't going to get oil into the combustion chamber, period. For this to be true, that would mean the valve cover holds combustion pressure, and it does not. Could maybe get fresh oil on the plugs when you remove the plugs if the holes are full of oil, but he said he had burnt oil on the plugs. Were the plugs loose?

For oil to get INTO the combustion chamber and onto the spark plug, either your valve seals are leaking, or your rings are shot, or maybe a HG problem but I'd think that's unlikely if you're not getting any cross-contamination. That's kind of all there is to it. Does it smoke on startup?

Perhaps a problem with crankcase ventilation given that there is evidence on all plugs. I know you said CCV was just replaced, but perhaps still the problem. you could try pulling off the intake manifold to see if there is oil everywhere on the intake runners.

Simplest, you could try running a slightly thicker oil than 0w-30, could just be seeping in....but given how much oil you said you found on the plugs, I am hesitant to think this is it.

edit: btw, its "yea" and not "yay" :)

danewilson77
09-26-2011, 05:06 AM
Change out VCG and associated spark plug gaskets, if you had oil in the spark plug well. Do the compression test if you only had serious carbon buildup on the plugs.

Hornung418
09-26-2011, 09:25 AM
zj96sc, when reading the OP, I saw:


Pulled my plugs and they were all black from burnt oil and the plugs from #3 and #4 were soaked in oil (esp #4)
and thus, my first response was to change out the VCG and torque it to spec. How often do dealers cut corners when they do a simple quick simple job like this? I'd feel much better about the situation if I know I did the work properly, myself. Simple elimination process.

Thanks for the other info regarding the blow by and the valve seals. What does a valve seal job look like for a DIYer?

Hornung418
09-26-2011, 09:32 AM
Dalton, did you manage to get pictures of the old plugs? I'd like to see what exactly the build up looks like in order 1-6. I just did some reading about the valve seals and that seems like a likely culprit, and looks like a relatively easy DIY with an Air Compressor and some pliers.

zj96sc
09-26-2011, 10:09 AM
Perhaps i should make sure we're talking about the same thing here. Covered in oil/burnt oil where? On the porcelain top portion of the plug? Or on the electrodes within the cylinder?

Above the threads, yes, VCG and grommets and associated sealing becomes suspect. Inside the cylinder, these aren't the problem.

You have to remove the cams and either the whole head or rotate each cylinder to shut the valves and hold the valves shut with compressed air. Then remove the springs with a spring compressor and swap the seals. I'd probably pull the head off if i was doing it and have the whole thing checked out.

#5:

http://farm6.static.flickr.com/5184/5561925881_e0a4279052_b.jpg
(from a thread on bimmerfest)

nike001
09-26-2011, 10:44 AM
Dalton, did you manage to get pictures of the old plugs? I'd like to see what exactly the build up looks like in order 1-6. I just did some reading about the valve seals and that seems like a likely culprit, and looks like a relatively easy DIY with an Air Compressor and some pliers.

I do not have pictures of the plugs, but I can fetch the plugs out of the top layer of my trash bag and take some (although they will not be in order of 1-6.. but they were all about the same minus #3 & #4 being a bit worse.



Perhaps i should make sure we're talking about the same thing here. Covered in oil/burnt oil where? On the porcelain top portion of the plug? Or on the electrodes within the cylinder?


Above the threads, yes, VCG and grommets and associated sealing becomes suspect. Inside the cylinder, these aren't the problem.


It was black and coated with oil on the electrode part of the plugs. It was mostly just black on all the cylinders.. with the worst ones being #3 & #4 and those were the ones coated in oil.

wsmeyer
09-26-2011, 10:57 AM
In the first post he said ALL the plugs had burnt oil on them. Leaking valve seal or piston rings would only effect a single cylinder. I think he needs to look for something that would introduce oil into the intake charge and thus effect all cylinders equally.

Pictures of the plugs would help too. Burnt oil and carbon buildup are both black but look quite different.

William.

nike001
09-26-2011, 11:01 AM
I just took pics of the plugs!! Waiting for them to upload!

http://i359.photobucket.com/albums/oo37/bsktsk8ter9/DSC_0846.jpg
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/DSC_0845.jpg
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/DSC_0844.jpg
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/DSC_0842.jpg
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/DSC_0841.jpg

zj96sc
09-26-2011, 11:05 AM
Yeah, I think we all (myself included) shot from the hip with perhaps not a perfect idea of what was going on. Apologies if I've offended anyone.

nike001: Exactly what was on the plugs? Did only two plugs have oil on them and the rest had carbon buildup? Are you sure it was burnt oil and not just carbon?

If we've got liquid oil on 2 plugs only and carbon buildup on the other 4, I suspect valve seals on cylinders 3 and 4.

If we've got burnt oil on all 6 plugs with liquid oil on 2 plugs, I'd suspect oil in the intake charge....CCV or related components.

wsmeyer
09-26-2011, 11:12 AM
On the 2nd and 4th from left I see a little bit of oil but IMO those plugs look about what I would expect from a car with 112K miles.

William.

nike001
09-26-2011, 11:16 AM
Yeah, I think we all (myself included) shot from the hip with perhaps not a perfect idea of what was going on. Apologies if I've offended anyone.

nike001: Exactly what was on the plugs? Did only two plugs have oil on them and the rest had carbon buildup? Are you sure it was burnt oil and not just carbon?

If we've got liquid oil on 2 plugs only and carbon buildup on the other 4, I suspect valve seals on cylinders 3 and 4.

If we've got burnt oil on all 6 plugs with liquid oil on 2 plugs, I'd suspect oil in the intake charge....CCV or related components.

Take a look at my pictures on page 2 and see what you think. Like I said before though, CCV was replaced last month with all new hoses & VCG was replaced about last november.


On the 2nd and 4th from left I see a little bit of oil but IMO those plugs look about what I would expect from a car with 112K miles.

William.

I noticed this as well. I think those are plugs 3 & 4

Hornung418
09-26-2011, 11:21 AM
What's the oil loss like? Are we talking about a lot of burned oil or is there a leak somewhere in the system. I'd check the oil pan and the OFHG...everything else looks to be Valve Seal related.

zj96sc
09-26-2011, 11:23 AM
yeah, i dont know that i see anything totally unacceptable there. maybe a little bit of valve stem seepage on 2/4 from left, but the rest look fine to my amateur eye.

I would maybe try running slightly thicker oil....why are you not using 5w-30?

You could also yank your new plugs out really quick and see what you see.

nike001
09-26-2011, 11:34 AM
What's the oil loss like? Are we talking about a lot of burned oil or is there a leak somewhere in the system. I'd check the oil pan and the OFHG...everything else looks to be Valve Seal related.

Seems to me like 1qt every ~1000 miles. No visable leaks anywhere. Me, Terra, and my buddy looked over a lot of it when we were doing vanos. Maybe I'll have a tech put it in the air at work and look around a bit more.


yeah, i dont know that i see anything totally unacceptable there. maybe a little bit of valve stem seepage on 2/4 from left, but the rest look fine to my amateur eye.

I would maybe try running slightly thicker oil....why are you not using 5w-30?

You could also yank your new plugs out really quick and see what you see.

I'm running Castrol 0w30 as per Terra's recommendation. He also suggested to try running even thicker oil.

I also thought about yanking out some plugs really quick to see what I can find. Maybe I'll do that later today If I have time.