danrx3

I posted this earlier today but for some reason it vanished. Oh well, here we go again:

Just had car serviced at 40,000 miles. Last service was at 25,000 miles. Am using Castrol Syntec Oil. I am the original owner and the car is used as a commuter with most of the mileage being highway miles. Car runs great except for some minor issues. Shop cut open oil filter and found some small silver metallic type particles. They dropped the pan and said the oil and pan looked free of metal. Is there anyone that can take a look at the metal fragments and oil and give me a good guess where they are coming from?

The shop thinks its the IMS bearing going. The car has been making a rattling/ball bearing type sound during the first 2-3 miles as the car warms up but this sound disappears after the car comes to temperature. Any thoughts?

If I have the IMS bearing replaced with an LN bearing, can anyone give me the names of the NJ/Eastern PA repair shops that have the most experience with this upgrade. Also, while I'm having the upgrade done, is there anything else that I should have done for this year and model car while the repair shop performs the upgrade?

Dan

Macster

Hate to sound like I'm kicking you when you're down but 15K miles between oil services too many miles regardless what owners manual says. However, the oil you are using comes in for high praise and the type of driving you're subjecting the car to is pretty easy on the engine relatively speaking so maybe it's a wash.

The noise you hear could be exhaust/heat shields rattling or even an exhaust leak. My second hand info is a going bad IMS bearing doesn't let the engine linger in the noisy but still running stage long.

Getting the cold car up in the air with the engine just started and the noise present will give you and tech a chance to identify where the noise is coming from. From the front or back of the engine cam chain related -- possibly. Heavily at rear of engine maybe IMS. In bellhousing clutch or input shaft. If exhaust related you'll hear noise coming from exhaust headers or from the heat shields.

Another test is to remove the serpentine belt and start engine cold. If noise not present noise from something in the serpentine belt system, or an accessory or accessory drive is noisy. Still worth looking into of course.

Metal fragments in the oil filter and none in the pan is not as serious as had there been both metal fragments in the filter and larger fragments in the pan.

From the description the metal is probably aluminum. The noise could be (could be) a chain guide that has lost part if not all its covering of composite plastic and the chain is dragging over the bare or nearly bare aluminum guide/tensioner rail.

The metal could have just come from some piece of metal flashing that broke loose. Not all engines shed this early on. Doesn't take much to when run through the pumps to look like a lot. Those pumps tend to make alot of very tiney metal flakes from just a piece or two of metal.

Post high res pics of the metal bits if you want. It will be hard to identify them by sight though cause they've likely gone through the high pressure pump and the low pressure scavenge pump so they're at best no better than indistinct metal fragments.

Check with flat6innovations or LN engineering to see if you can get a list of shops in your area that can perform the work you seek.

If engine starts making more noise, or running rough, doing anything out of the ordinary shut it off first and ask questions later. I've seen one 996 engine shut down in time to make the engine rebuildable by the replacement of a few items damaged when the IMS bearing failed. One item was a cam chain guide rail's composite plastic covering.

Sincerely,

Macster.

redridge

use a magnet... if it sticks... it could be bearings. If it doesnt stick... should be OK.

danrx3

Thanks for the advice.Will definitely have all areas checked before deciding what to do. Local garage recommended the 15,000 mile intervals between oil changes. From now on will go with 5-8K intervals.
Dan

PJorgen

If you still have the old oil, send it out for analysis. I use Blackstone Labs (http://www.blackstone-labs.com/). About $20 for a very thorough analysis which may help in your diagnosis.

jasper

Hey - this Macster guy is good. I've noticed this before but his advice is really good this time.

My vote is tensioner/chain guide related.

I also like the magnet test...although as Macster has stated if the bearing has come apart, you wouldn't still be driving the car from what I've heard.

Get it fixxed and tell us what the deal was please....and yes shorten up those oil change intervals.

danrx3

Dropped car off today at shop in NJ that only works on Porsches. They will analyze metal fragments and scope engine with fiberoptics to let me know where the metal is coming from. I'll keep everyone posted on the results. Thanks for everyone's recommendations.

danrx3

Just got car back from Powertech. They checked the rms, flywheel, clutch, chain tensioners, tensioner rails, and IMS bearing. All were in good condition. Replaced/upgraded the 3 tensioners and IMS bearing since they had it apart. Replaced the oil pan with a deep sump oil pan. Replaced plugs and ignition coils. Upgraded oil filter with a spin-on kit. Upgraded thermastat with a low temp T-stat 160. Upgraded air intake with a K&N system and modified software using upsolute-p. Car runs great. Still not sure where metal fragments are coming from? Any ideas where to look next or is this considered normal wear for this car?

redridge

its not uncommon to have metal frags (tiny chips, not chunks) in the filter.... these cars get faster when they loosen up. I read one long term review of the 996, after 45K miles.... it was faster from 0-60 when it had 5k miles.

How did you like powertech?

Macster

Since many of the problem areas were checked and nothing found amiss hard to say what if any thing serious is pointed to by the metal bits.

Chain guides, tensioners, an IMS bearing ugrade? Engine will probably outlive us all. I assume chains given a thorough check out looking for bad rollers? Could have been a valve spring but if a valve spring bad enough to be shedding metal bits you'd hear the valve making noise.

Still not clear as to what kind of metal and how much and in what amount. Usually, but not always an engine has shed all the metal its going to at 25K miles. But there are exceptions. Metal flashing can break loose and almost certainly if it does it will end up in the oil sump and hence through the pump and into the filter.

I'd advise you to keep an eye on things, but with spin on filter you'll have to cut filter apart now. I prefer the OEM housing setup with the filter cartridge.

Not sure K&N filter an upgrade. Tricky to clean and reoil properly and if not done right either filter not as effective as stock or filter oil can foul MAF.

I'd say about all you can do at this time is just drive the car and enjoy the heck out of it.

Sincerely,

Macster.

falcon7x7

+1 Macster is da man!!! He is a wealth of GOOD info!

danrx3

Just had 996 serviced at 45,000 miles. Filter was clean (no metal particles), so it seems that whatever work I had done at PowerTech seems to have solved the issue. Car is running great.

rpm's S2

Thanks for the followup. These extended service intervals are ridiculous.