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YOUR RESEARCH2004 996 C2 Engine quit
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Check oil filter and there's metal in it
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Performed · outcome unconfirmed · Original poster
My mechanic has told me this morning that he checked the oil filter and there's metal in it.
Leading evidence: 'Check oil filter and there's metal in it' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check oil filter and there's metal in it' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Install pelican bearing myself, the original one looked
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Performed · outcome unconfirmed · Original poster
I installed the Pelican bearing myself, the original one looked to be in perfect condition.
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Performed · outcome unconfirmed · Original poster
I changed the ims and rms as preventative maintenance.
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I had replaced the IMS bearing and bolt with the Pelican Parts kit just a couple of months ago.
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I drained and refilled the coolant and replaced the water pump with a Gates brand aftermarket unit about 1000 miles ago.
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So I have a follow up to the rattle sound I was hearing and posted about previously- (described as a clatter or knocking sound when at partial throttle and between about 2500-3500 rpm).
The engine quit running 2 days ago while stopped at a red light. It was at normal operating temperature and I had driven about 50 miles already that day, 10 just prior to the engine dying. It was running normally right up until when it stopped. My girlfriend was driving and I though maybe she just stalled it- but it wouldn't even turn over with the starter. I pushed it clear of the highway (about 100 yards to the next street, thank you to a random stranger who hopped out of his car and helped me push!)
It seemed like the battery was low as the engine wasn't turning at all. I connected a portable jumpstart pack I keep in the car and after 5 minutes tried it again. This time it fired up briefly and ran very rough with an awful mechanical sound- I shut it off immediately. It is now at the independent Porsche mechanic shop in my area. The mechanic has an excellent reputation and I'm sure he will be able to find the cause- I'm just hoping the motor isn't ruined!
My best guess is that the water pump seized and induced enough drag to stall the at idle engine, and then the starter motor didn't have sufficient torque to rotate the engine with a frozen water pump (Though i suspect it would be able to just drag the belt over the pulley if it were frozen stiff). There were no fluid leaks at all and no indications in the coolant tank or on the oil dipstick of intermix, but I did note some small black particulates in the coolant tank. I drained and refilled the coolant and replaced the water pump with a Gates brand aftermarket unit about 1000 miles ago.
Does anyone have a different guess? I'll update this thread with what my mechanic discovers.
Does the Gates brand have metal or plastic impellers? When a water pump goes out of wack, with plastic impellers they just break as to not damage the block. So with one of those, it shouldn't seize the engine. You can start the engine without aux belt for a short period of time though, although mechanical noise doesn't sound good.
Do you have any soundbites of your rattle and/or the mechanical noise?
Yea, there is pretty much no way a water pump impeller is going to stop the engine force. It would only take a few HP to shear it to pieces. I don't think you're going to find anything good in there. Sorry to say that, but hoping for the best.
Thanks for the replies. The impeller blades on the replacement water pump were plastic. Still no word on the outcome. And unfortunately I don't have any recordings of the sound it made.
It's hard to say. I only heard it for about 3 seconds (upon starting the engine after it had just died). It ran with a terrible clatter noise accompanying it, and I shut it right off. I had replaced the IMS bearing and bolt with the Pelican Parts kit just a couple of months ago. It went in easily and I'll really be surprised if it is an IMS bearing failure.
So sorry to hear this.
You should have never restarted your car! That may have caused an additional $$$ in collateral damage...My timing chain broke and PO tried the restart. I'm in the same boat!
Similar thing happened in my 1999 C2.
Stopped at a red light & my car died. Restarted it, and it died again almost immediately.
I knew it wasn't good when I saw coolant pouring out the exhaust as the wrecker was loading it up.
I knew better than to start it... But I had no idea why it died and I didn't hear any sounds when it happened. My mechanic has told me this morning that he checked the oil filter and there's metal in it. So now I'm on the hunt for a rebuilt motor.
Im not sure trying to restart it caused that much more damage. For metal to show up in the filter, it got there before the engine died most likely. These engines probably shed material before they slow down enough to stop and it still takes a little time for metal to enter the filter. I assume the oil filter is immediately after the oil pump? Which means that metal would have to come off the engine, get returned through oil passages via scavenging, or fall into the oil sump pan before being sucked up by the oil pump and pushed into the filter.
So it progressed from a light rattle/knock at 2500-3500 rpm, to a stall/no start, then start with intense rattle and metal in the filter..Maybe a failure analysis (autopsy) will shed some light on how and why this progressed in that way. Sorry for your loss.
Yes, Porschetech3, it progressed as you've said. Light rattle/knock at mid rpms, then stall/no start, and then start with an intense rattle. I checked out the metal drained from the filter today and it's very fine (ferrous) dust (there are probably larger pieces in the oil pickup screen. Definitely something gone awry in the crankcase. I'm searching for a replacement engine now. Once I get this one pulled I will at a minimum examine the IMS bearing. For now it's a mystery.
We haven't dropped the sump. I'm assuming due to the engine clatter noise and the metal in the filter a full teardown and rebuild would be in order to reuse the engine, so I don't want to pay for the labor to just see what happened.
I saw a thread here recently that Porsche is now selling long blocks for 6500 if memory serves. someone here recently got one and installed it and it went well.
I would contact
https://norspecdismantling.com/
for an engine. I have got so many parts from them including a tranny for 996 and new top for my 986. Best in the country from a service perspective.
Sorry for your loss.
The smaller particles look like failing IMS bearing, but then you have that smiley piece that is much bigger; perhaps big end bearing or crank thrust bearing? any milkshake?
That's not ims. No glitter. That's something just as bad or worse. Time for teardown, if you haven't decided to go down that route already. Depending on the damage, the core might or might not be suitable for exchange.
Was this car tracked at all? What led up to the failure?
I've only had the car for about 6 months but the PO told me he never tracked it. The only indication prior to the failure was a light rattle sound at mid rpms. The IMS had just been replaced with a pelican parts bearing about 1000 miles before.
I've elected to replace the engine with a used one from a wrecked car. It came of a 2002 C4 with tiptronic and 61000 miles. My mechanic just received the engine and called to tell me it's a M97 motor- but I'm guessing it's really just a newer M96 with the larger non-replaceable IMS bearing. I had asked him to put in a LN Engineering ceramic bearing (when we though it was an original M96).
I don't like when owners put in an IMS bearing and then immediately sell the car. It's a red flag in my book, especially if they went the cheap route on the Pelican kit. I've seen people specifically use that one since it has a sealed bearing, to try to limit debris from damaging the new bearing. The fact that you found debris in the engine points to possibly prior damage, perhaps from a failed IMS. But who knows for sure.
Do you have a receipt for who installed the IMS bearing - perhaps you can ask them about what was the condition of the original bearing or any other info about the history of the car (and engine)?
If it is an 06-08 non-serviceable M97 bearing, just have the grease seal pulled as preventative maintenance:
http://imsretrofit.com/my06-08/
I installed the Pelican bearing myself, the original one looked to be in perfect condition. Previous mechanic reports indicated rough running due to a split oil filler tube and a potentially failed front crank seal. I found an additional air leak at one of the corrugated hoses connecting the passenger side head to the AOS. Up until the engine failed it was running pretty well.
Be sure to bore scope the cylinders and pull the oil pan before you install the used replacement engine. You don't want any surprises.
For bore scoping, you'll need to go through the sump with each piston at TDC to be able to inspect the bottoms of the bore. That's where scoring starts.
I realize you�ve moved on to another motor, but wondering if you decided to try to pinpoint what ultimately happened? You state previous mechanic reported a possible crank seal issue, any clue what that was based on? Lowpure mentioned the image you posted looked like his after a crank bearing failure. Flat6 mentioned it didn�t look like an ims failure given there is no glitter present. Did you simply change the ims as PM or was there a catalyst for the change. Your thought are much appreciated in helping to further document another M96 failure.
I changed the ims and rms as preventative maintenance. The rms actually looked ok but was of the old design. The aos flange was leaking slightly but the bearing looked perfect after 90k. I think the mechanic notes about a potential front crank seal were due to a worn serpentine belt that snapped and got threads wrapped around the pulleys, etc on the font of the motor. That, and a cracked oil filler tube resulted in an oily mess around the front (rear facing) of the engine. The front crank seal turned out to be fine.
I’ll ask my mechanic to scope the cylinders of the replacement engine before install and check the pan for debris. I do plan on opening up the failed engine to determine the actual cause of the failure if it isn’t readily apparent once it’s removed. I’m interested in rebuilding it as a spare if possible.
Hi . I have exactly what you describe - sounds like coffee beans in a can. All started when I lost the water / I assume pump failed.
What does it mean if I have that sound? Many thanks Sue
