Timing Belt Cover Residue

Tatnic · Post by **Tatnic** » 16 May 2009, 15:13

New Poster here...just bought a 2001 S40, 1.9 turbo, 115,500 miles and drove it home today (100 miles). Ran nice and smooth and strong, no problems, no studders, nothing.

It's due for a timing belt so when I got home I popped the cover to take a peak, I was curious to see its condition. The belt looked good, no hairlines anywhere, not even over the pulley. Its a german belt, so should I assume its the original? No sticker on the cover. If it looks that good does that mean it has a lot of life left or should I be planning a replacement anyway??

When I opened the cover, I noticed a black, oily residue on the inside of the cover, right opposite the exh. cam. Same residue coming out the pipe....the previous owner had put a bunch of crap in the gas because the CEL was on. Would this explain this or is there a PCV problem or worse?

Thanks for any insight.

Tatnic

Post by **vegasjetskier** » 16 May 2009, 17:05

Can you post a pic or two?

Tatnic · Post by **Tatnic** » 16 May 2009, 19:00

I can't wiithout dismantling it. I just pulled the cover back to take a peek at the belt and noticed the residue in a circular pattern. The pattern was formed by the exh. cam pulley. Bad seal? PCV problems? VVT shot?

Anyone seen this before?

Post by **MadeInJapan** » 16 May 2009, 21:12

The cover comes off easily- One bolt I believe or it could be two...anyway, take it off and shoot us a picture.

Tatnic · Post by **Tatnic** » 17 May 2009, 06:45

I tried to take a pic but the black residue on the black cover can't be seen clearly...so let me paint a different picture.

If you picture a see-through, clear upper cover and are looking straight onto the side, then you'd clearly see the exhaust cam pulley and black residue along the top edge of the cover, from about 9 to 12 o-clock. The residue would not block the view of the pulley. Bad cam seal seems obvious to me and if I change the belt then I'd change the cam seals too.

But if the reason the cam seals are leaking has to do with poor maintenance clogging the PCV system, then how is that addressed, i.e. cleaned?

thanks for your help!

Post by **MadeInJapan** » 17 May 2009, 07:14

How old is the belt? It could be PCV but if related and you have oil on top of the engine, it could be spilling over onto that area- but I would think more would be wet with oil- The reason I ask about the belt itself- my fear is that the "black" belt itself is being chewed up a bit and what you're actually seeing are little bits of the belt that are being deposited in that area- makes sense.... if you're in there anyway for a part change, yes, definitely change that belt. As you say, it's obvious that it's the cam seal under the cam gear, that's not that big of a deal, but you'll have to make sure and mark the cam gear BEFORE taking the belt off- clean up the area and use some spray paint across the cam gear to the side of the engine so that they line up before you put the gear back on...I believe it can go on two ways and you don't want to get this off... pull the seal out with a pick or something that can grab it without scoring the softer aluminum and push the new one in (right direction) flush with the opening- you can see how far the old one was in- best way to do this is to find something the exact diameter of the seal and push it in so that it is not crooked- otherwise you'll get another leak. Both www.fcpgroton.com and eeuroparts.com sell the seals for your car. Good luck and let us know how things go.

Tatnic · Post by **Tatnic** » 17 May 2009, 07:42

MadeInJapan wrote:How old is the belt? It could be PCV but if related and you have oil on top of the engine, it could be spilling over onto that area- but I would think more would be wet with oil- The reason I ask about the belt itself- my fear is that the "black" belt itself is being chewed up a bit and what you're actually seeing are little bits of the belt that are being deposited in that area- makes sense.... if you're in there anyway for a part change, yes, definitely change that belt. As you say, it's obvious that it's the cam seal under the cam gear, that's not that big of a deal, but you'll have to make sure and mark the cam gear BEFORE taking the belt off- clean up the area and use some spray paint across the cam gear to the side of the engine so that they line up before you put the gear back on...I believe it can go on two ways and you don't want to get this off... pull the seal out with a pick or something that can grab it without scoring the softer aluminum and push the new one in (right direction) flush with the opening- you can see how far the old one was in- best way to do this is to find something the exact diameter of the seal and push it in so that it is not crooked- otherwise you'll get another leak. Both http://www.fcpgroton.com and http://www.eeuroparts.com sell the seals for your car. Good luck and let us know how things go.

its oil...in fact, there's a stream of it extending down onto the lower cover and it looks like its been doing this for awhile. There are no bits of rubber, just graphite, oily residue (combustion residue). The belt looks good as I said previously.

So any opinions on the PCV system? Why is exhaust getting past the exh. cam seal? Is it simply a bad seal or is there excessive pressure pushing the past the seal because of a plugged PCV system? And if so, how do I "fix" this.

thanks for your help.

Post by **MadeInJapan** » 17 May 2009, 08:44

Yes, a clogged PCV can cause excessive pressure to push past the seals...actually it's good that that one went and not your lower or rear main seal. With the car idling pull your dipstick to see if there is pressure/smoke coming out- if so, then you have positive pressure and you'll need to clean or replace your oil trap and related hoses (this is the PCV system). Btw, where the hose connects at the base of your large accordion intake hose (from your air filter box) should be clear and without blockage- this is pretty easy to fix...just use some pipe cleaners w/ bristles with alcohol or even brake cleaner and ream it out until it is clear all the way through the accordion pipe- This is called the PTC nipple and if it is not clear, it will act the same way as an entire clogged PCV system. That would be my first step. If this is clear and you still have positive pressure, then your intake manifold has to come off to clean/replace the oil separator (breather box) and related hoses- it's quite a big job.

Tatnic · Post by **Tatnic** » 17 May 2009, 09:30

thanks for you help MIJ. I was hoping for an easier fix to the PCV system but I suspect you are right in the severity. I don't think I'll replace the cam seals until I address the underlying problem.

How does one prevent this from happening in the first place? Is there routine/preventative maintenance for the PCV that helps to reduce or at least slow the process of plugging?

thanks again.

Post by **MadeInJapan** » 17 May 2009, 12:44

They all have to be done at about 100k miles or a bit more depending- the 60K mile service calls for the PTC nipple to be cleaned at least and this is good maintenance. Besides that, change your oil on time and if you can switch to synthetic oil, this will help (if you have a turbo, you should be running it anyway)...but, even so, the rubber lines tend to get hard and begin to crack by about 10 years (necessitating a complete replacement of the PCV lines anyway)...I replaced what I could recently on my 850 with silicone lines- These won't get hard and brittle but they still may clog.