help identifying metal in oil sump please - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Hi, working on "preventative" IMS bearing replacement, 2001 boxster-s automatic. Turns out it is a dual row bearing and seems to be fully intact and functional. Did see metal specks and 2 slivers in drained oil so decided to check the oil sump and removed cover, not a speck of metal laying in the sump cover, but a teaspoon of what looks like mangled spring caught in the metal strainer. 2 other bits in top right, may be plastic? Engine did make an awful noise, for the first time, as i moved it to the work area for the lift. Any thoughts on the source of this metal, to guide me on what should be done next? Thanks, Garry

Very interesting. Imho the only spring inside the engine is 996 107 127 53 (regulates oil pressure). I recommend to check if it is still in place which is easy, but unbelievable that it could make its way into the engine tbh.

The oil pressure spring is similar, but nowhere near that long: I have no idea what that could be, but it's also hard to tell what size it is, perhaps a banana for scale? As an aside, this is what I found in my strainer when I took my pan off:

OT: You've done it. I've got to change the oil in 500 km, and now it's time to take the sump off! My mind's racing right now!

Thanks for the thoughts. This is pic for scale, looks like about 1.5mm diameter spring????? could have been very long, or multiple shorts??? It is definitely magnetic/ ferrous, feels like spring/hardened steel. I have seen similar sized "springs" circumferentially in bearing seals, for compression i believe. My dual row bearing seals appear intact but if I spin it i see a little oil seep out. If I understand a sealed bearing, oil should not be in there??? Could mean the circumferential compression "spring" was spat out with the seal visually intact?? Hard to imagine..... I guess the next step is to pry open the seal to inspect the bearing? Nobody would consider putting the original dual row bearing back in if functional, would they? Is there another large sealed bearing in the engine that could have lost it's circumferential compression "spring", that i need to be considering?

You should never reinstall an extracted IMS bearing; the process of removing it destroys the ball bearing cages inside the bearing. The spring is most likely from either the front or rear main seals.

Thank you JFP! 1. loud and clear on getting a new IMS bearing, thanks! 2.RE: my unprepped IMS cover removal with now uncentered IMS shaft: how bad is this? 3. Main seal spring: thank you for sharing your suspicion as the source of the spring. The rear main seal is not leaking from the outside. Is it still a possible source? Should I start planning replacement of both front and rear seals? Or start with the accessible RMS even though no leak? Cursory impression is no oil leak from front of engine, all the old oil buildup seems to be towards rear of engine, never had drips to the floor. 4.I do not know the inside of the engine at all: could the spring have come loose, become ground-up and made it to the oil strainer (no sign of bits elsewhere so far) WITHOUT causing severe engine damage? In other words, is this potentially salvageable, or quit? thanks, garry

On a five-chain engine, you are locking the exhaust cam on one cylinder head. In reality, you could lock either side, but the passenger side head, with the green cam cover plug towards the front of the car is way easier to get at and see if the cam slot is in the correct position, so it is the one preferred by those of us that do this on a regular basis and need to work quickly and cleanly. The third hydraulic tensioner is underneath the AC unit on the top of the engine. If you removed the IMS flange cover with the engine locked at TDC and no cam lock in place, you have a better than even chance that at least one chain has jumped time, usually indicated by the IMS shaft pulling to one side. With the shaft in this position, you cannot pull the bearing out, and the cams will need to be reallocated to get everything back to where it should be. That would require access to some special tooling and knowledge of how the cams are allocated. This process is not hard but is complicated and cannot be done without the correct tool. The only place that spring could have come from is either front or ream main oil seals. In any case, you should be replacing the RMS with the new PTFE upgraded seal whenever doing any IMS work as it is a $20 part and accessible when the trans is out but again requires a special tool to install it correctly. LN rents this tool for DIY installs. They may also have the cam allocation tool as well, but you will need to check with them on that if you need to do the cams.

This information is invaluable to me JFP. Firstly do you think so much mangled spring material could have made it to the strainer with a decent chance of no engine damage? (if engine is likely damaged it would not make sense to try correct the jumped chain, IMSB, RMS etc???) Secondly, the IMS is off to the side as you mentioned. Presumably this makes it more likely that a chain has jumped? For what it's worth the bearing did pull out without difficulty. Not sure if this extraction has made matters worse..

The spring probably did not do any damage; we have seen the entire trust bearing fall into the sump relatively intact, with little damage other than to where it normally sits in the crank carrier. But, in any case, you need to pull the RMS first to see if that was the source, if it isn't, then the crank pulley and front main seal comes out next. As for the shaft being off center, the real problem will come up when you try and replace the IMS cover flange, you may have to correct the cam allocation just to get the cover back on

You were right JFP, despite no leak, the inside of the seal was stripped bare! So the next step would be to tackle the chains I guess> To be sure timing has not jumped and to center the IMS. Should I just plan on replacing the chains etc which I have seen described as high wear/maintenance items? thanks again

Great outcome! Chains and pads would be my suggestion.

I would be looking at the chain pads between the cams, they are subject to excessive wear. The long chains tend to do better, and they are a major pain to try and change with the engine still in the car.