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I inspected my oil filter during my oil change this weekend and found these black bits in there. They look like hard / black plastic bits and I saved the larger ones I found. Possibly from the chain guides. What do you think?
I do have occasional chain rattle episodes on cold starts after the car sits a couple of days (loud but for just a second). I am looking into replacing the IMS chain tensioner soon just in case.
I also send an oil sample to Blackstone to see what it says since the bore scoring scare is getting to me.
Have all 3 of your chain tensioners changed immediately. That's tensioner guide plastic. If you break off or wear all the way through those, you're done and the chain will start grinding into the metal tensioner paddle itself until the chain wears enough that it snaps and the engine loses timing and self destructs (bent valves, ruined pistons, etc).
The Blackstone analysis won't detect any of that plastic stuff. The shop that changes them could also pull your sump plate to see how much more of it (if any) is stuck in the corners or in the pick-up screen so you can determine if you should have the chain guides replaced too or if just fixing the tension problem eliminates the chain slap that's knocking the bits of plastic free.
Have all 3 of your chain tensioners changed immediately.
Pete, I changed 2 of the tensioners, leaving the one under the A/C compressor for another day. If you were judge which tensioner/paddle is the first to go, which would it be? In other words, how much did I help myself by replacing only the two easily accessible ones? I did them preemptively - in other words - no symptoms and at days-long cold start, no appreciable change in engine sounds between the old 2 and the new 2.
Pete, I changed 2 of the tensioners, leaving the one under the A/C compressor for another day. If you were judge which tensioner/paddle is the first to go, which would it be? In other words, how much did I help myself by replacing only the two easily accessible ones? I did them preemptively - in other words - no symptoms and at days-long cold start, no appreciable change in engine sounds between the old 2 and the new 2.
Hard black plastic is the IMS Tensioner wear pad. All the other wear pads and chain guide rails are the brown plastic.
By changing 2 of the 3, you helped yourself 67%. No way to really know which one gets lazy first and starts the chain rattle without seeing what color plastic pieces are being captured. If you didn't and still don't have chain rattle on start-up then you should be good, and took a positive step in preemptively replacing the two that you did. I'd do the 3rd one when you can work it in too.
Pete, I changed 2 of the tensioners, leaving the one under the A/C compressor for another day. If you were judge which tensioner/paddle is the first to go, which would it be? In other words, how much did I help myself by replacing only the two easily accessible ones? I did them preemptively - in other words - no symptoms and at days-long cold start, no appreciable change in engine sounds between the old 2 and the new 2.
What condition were the replace tensioner pads in?
What condition were the replace tensioner pads in?
I believe he replaced the tensioners themselves and didn't do anything with the pads - that's not as easy a job since they're inside the motor, especially the IMS tensioner paddle pad, which is about as deep as you can get in the belly of the beast.
What condition were the replace tensioner pads in?
As Pete said, just the two easy tensioners (not pads). But, by inference, the pads can't be too bad since when I inspect my oil filter medium I see what I think is only a trivial amount of black or brown specs (maybe 3 on the whole medium and always 2 mm or smaller). I have not had my sump cover off during my ownership so I can't comment on any foreign object contents there.
As Pete said, just the two easy tensioners (not pads). But, by inference, the pads can't be too bad since when I inspect my oil filter medium I see what I think is only a trivial amount of black or brown specs (maybe 3 on the whole medium and always 2 mm or smaller). I have not had my sump cover off during my ownership so I can't comment on any foreign object contents there.
Maybe the 996 is different? On the 996, mk1, for the tensioners to come out, the headers must come off, the valvecovers must come off, the cams on one side must come out, and the pads are right there. I know Porsche changes the solenoid accessibility in the mk2 996, and with the 997, maybe they made tensioner removal much easier/better. The mk1 is a 5-chain Motor, too, maybe that’s the other reason.