PeaCar

Hi all,

ive been searching lots over the past 24 hours but I can't really get to the bottom of something.

yesterday I was starting the LN engineering upgrade of the single row IMS in a 2000 911 3.4. 80k miles.

upon removing the oil filter, I found tiny bits of black hard plastic. There were also a few pieces stuck in the sump pickup tube screen. I'm talking small, other than a few bits large enough to get loved in the screen.

there is no metal whatsoever. I checked with a magnet, no shiny bits.

what the hell does one do now?

tensioners, paddles, IMS, fear, lost sleep, nightmares. there's so much buzzing around my head I'm lost.

bottom line, engine runs fabulous, other than an odd ticking noise here and there at idle sometimes everything else is just super perfect.

Montychristo128

Chain ramps are black plastic. Not too worrying, I would not lose too much sleep.

dgjks6

Don't worry. Be happy.

Not an IMS expert, just a previous IMS sufferer. Plastic is not as bad as metal. But you still need to find the cause. Pull the old bearing and inspect. If not from there probably chain tensioner related. Look for pics here on the site and see if any match up. IIRC, the detrimental problem with the plastic is that it can cause plugged oil channels, so I see frequent oil changes in your future.

Woodman71

I can see the infomercial now: "Do you suffer from irritable IMS? Sleepless nights, hemorrhaging wallet, and cantankerous wife? Worry no more! Now, there's a solution!"

PeaCar

Thanks guys!

so, life goes on?

Install LNE IMS bearing and continue living life?

PeaCar

Well, wasn't much play in my IMS bearing, but when I pried the seal off, I found it was filled with only motor oil that smelled a little burned. No metal inside the bearing though.

btw, I found a few tiny aluminum flakes upon taking the engine apart. But like, I don't know if it's from taking the tensioner side out of the holes and stuff.

the mechanic doing the work with me said my engine is amazingly spotless and looks absolutely fabulous in every respect. Crisis averted?

the bit of debris in the oil filter has me a little worried, mechanic thinks I'm overacting and said all engines will shed a few metal flakes over time.

thoughts?

dgjks6

"but like" in a sentence? Are you really old enough to drive?

OK - got that out. Few small metal flakes is normal. Few. Small.

What did you mean taking the engine apart?

PeaCar

Apologies there, on occasion, especially when stressed, I type my mind and don't correctly engrish.

Im not old enough to drive, but my mom says if I get an A on my spelling test this Friday I can AutoCross the 996 on Saturday.

forum searching has really destroyed the fun of these cars for me. After 7 years of aircooled, I'm astonished some of you are brave enough to turn the key of a water cooled flat 6. These engines are both impressive and very dissapointing.

By "taking the engine apart" I meant to say doing the IMS bearing. If you have ever done one with the engine in the car, I think you would know just how unpleasant it is. The fun of disconnecting fuel lines behind the throttle body to get out the A/C compressor starts to really strip a lot off the car. Looking at how many parts are now off the car to do this job has me really surprised.

AWDGuy

once the trans is removed, the IMS bearing is very accessible.

I'm not following the logic to remove the motor to do a IMS job

AWDGuy

I lol'd. awesome reply.

dan_189

The struggle is real, just as rennlist is amazing and frighting at the same time!

Head up and stay one step ahead in terms of maintenance

MiataR

It's true... I already have my 2nd batch of "preventative maintenance" scheduled for later this year.

If I had never joined RL, I would be a richer man.

Now go drive you car!

PeaCar

i really want to, but man, I don't feel awesome about it. I guess I just need to get in and go. I'm worried I will start seeing oil filters in my dreams.

does anybody here suffer from 996 nightmares?

Macster

Reads like your mechanic is a good one.

The engine is basically aluminum. Over time the engine will shed a piece of aluminum that after it possibly goes through an oil scavenge pump and through the high pressure pump gets smashed very thin and breaks up into smaller pieces. Normal unless the amount of aluminum in the oil has the oil looking like metalflake paint. (Even then this can be normal if the engine is new and one is doing the 1st few oil changes.)

A few tiny pieces of dark plastic -- really dark almost black -- is probably from the crankshaft to camshaft chain drive chain tensioner rail. IIRC this rail is the darker plastic, the other rails for the chains that run from the IMS to the exhaust cams and from the exhaust cams to the intake cams are a lighter color, brown, a dark caramel.

A few tiny pieces is not really worth getting worried over. The pieces at the oil pick up screen were probably there from day one. Over time a piece can break off and flow into the oil pump and then if one examines the oil filter housing oil and looks at the filter element he'll spot the tiny pieces.

If you want do an early oil/filter change after the IMSB is installed. After an engine is disturbed this almost always results in an uptick in debris shedding so be prepared for what you find. It won't be a lot but it will be more than you might think.

If you want then you can after a number of additional miles do another oil/filter service and I expect you'll find the amount of debris way down.

docmirror

Weird, but in the lower left of the pic, there appears to be an uncaged, silver ball bearing sitting on the flange of the case? What's that all about?

Tiny Al flakes are usually flashing from the engine case, or the oil pan, or something. Usually nothing to worry about. Now that your car is laid up, it would be a good time to replace the cam chain guides which most likely are the source of the black plastic bits. In the case of plastic, it's now 17 years old, and has gone through many heat cycles. It's getting more brittle, and prolly ready to be replaced based on age if not condition.