997.2 3.8 Engine Failure
RL Community Team
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From: Atlanta
My indy gave me great advice... he was an ex-Porsche shop forman.... he said something like "If it is under warrenty and you hear bad noises, gun the engine! Blow it up! You would rather have them replace it than repair it."
Peace
Bruce in Philly
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From: Maryland
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From: SE Wisconsin
I would repair it and see what happens. Either you put a new tensioner and starts and runs smoothly or it sounds like a box of rocks. Should take about a second to determine. The flecks in the filter are concerning but nothing really in the pan. I would have expected to see anything metallic, not just a fleck of flashing. Either you have a major engine problem or not. You had an obvious issue with the tensioner and no metal in the pan, at this point running for a couple seconds wouldn't hurt anymore than the time spent making the video at the top.
Edit: I missed the part about the metal piece being attracted to the magnet. Admittedly that's a problem, obviously not a piece of aluminum flashing. I don't think it changes my assessment on running it for a couple of seconds to see if the noise goes away.
Edit: I missed the part about the metal piece being attracted to the magnet. Admittedly that's a problem, obviously not a piece of aluminum flashing. I don't think it changes my assessment on running it for a couple of seconds to see if the noise goes away.
Last edited by Prairiedawg; Dec 30, 2018 at 08:13 PM.
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From: Florida
Pulled out the tensioner this morning. First of all the pivot bolt for tensioner lever was not even tight, i was able to undo it with my fingers! Secondly the bushings are very loose and can be seen in this video. Prettt sure theyre not supposed to be like that but i will compare once i get the new parts from Pelican.
http://youtu.be/pWmeO_MKasU
http://youtu.be/pWmeO_MKasU
Burning Brakes
Joined: Oct 2009
Posts: 860
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From: RI
Originally Posted by sandwedge
Maybe I'm not thinking this through as I should. Even with the tensioner being in the condition you describe, how would metal and plastic particles from it make it into the engine oil?
Racer
Joined: Mar 2015
Posts: 288
Likes: 34
From: Iowa
If this was my engine I would not start it. While the bad tensioner could definitely be the cause of your noise it does not explain all the ferrous metal in your oil. That is fact. The used oil analysis will be interesting but doesn't change anything regardless of results. This engine needs to be investigated internally probably starting with the timing chain. I think ignoring this will only result in more expense in the end. Any codes? Over rev report?
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From: Livermore, Ca
Bronz, first of all thank you for taking the time to post all of the data. It takes time, Adding knowledge to this forum (or any) and taking knowledge from it is invaluable to us.
Metals containing iron are ferrous, thus magnetic. The brass, alum, and misc other non-ferrous metals obviously wont attach to the magnet in the drain plug (non-stock?)
Charles N contributing to this is very very helpful.
So, the tensioner will definately make those noises (heck, resonates thourgh the entire car).
After tensioner replacement, will you still be taking it to an Indy or just waiting on the oil analysis? sorry if i missed prior answer to my question....
Anyways, Happy New Year to y'all....
Metals containing iron are ferrous, thus magnetic. The brass, alum, and misc other non-ferrous metals obviously wont attach to the magnet in the drain plug (non-stock?)
Charles N contributing to this is very very helpful.
So, the tensioner will definately make those noises (heck, resonates thourgh the entire car).
After tensioner replacement, will you still be taking it to an Indy or just waiting on the oil analysis? sorry if i missed prior answer to my question....
Anyways, Happy New Year to y'all....
Pro
Joined: Dec 2017
Posts: 657
Likes: 98
From: Arlington, Texas
OP, this thread is certainly getting a lot of attention. I'm sure you're concerned about the outcome. My opinion again is that you don't have internal engine failure. I'm not a professional technician, just an average DIYer/enthusiast like many here. Here's how I see it:
1. Initial concern was a loud knocking sound, as you showed in initial video. Check Engine Light not activated.
2. You had two prior UOAs, each showing no concerns.
3. Filter had some ferrous particles. Dropping pan reveals two pieces of plastic or sealant and one piece of metal. In your pictures the pan looks clean otherwise, as does the oil pump intake screen.
4. The serpentine belt tensioner has failed. I believe you said belt wasn't in good shape. You've ordered a replacement tensioner and prolly a belt too.
5. I think pending oil analysis is coming back clean. The particles you found are too big to be seen by standard analysis.
6. Only other thing I can think of before putting it back together is to pull the spark plugs and check cylinders with a borescope. Replace spark plugs if indicated.
Other that I'd put it back together and start it. Assuming it sounds normal I'd run it 300-500 miles and pull the oil filter and examine it.
1. Initial concern was a loud knocking sound, as you showed in initial video. Check Engine Light not activated.
2. You had two prior UOAs, each showing no concerns.
3. Filter had some ferrous particles. Dropping pan reveals two pieces of plastic or sealant and one piece of metal. In your pictures the pan looks clean otherwise, as does the oil pump intake screen.
4. The serpentine belt tensioner has failed. I believe you said belt wasn't in good shape. You've ordered a replacement tensioner and prolly a belt too.
5. I think pending oil analysis is coming back clean. The particles you found are too big to be seen by standard analysis.
6. Only other thing I can think of before putting it back together is to pull the spark plugs and check cylinders with a borescope. Replace spark plugs if indicated.
Other that I'd put it back together and start it. Assuming it sounds normal I'd run it 300-500 miles and pull the oil filter and examine it.
Three Wheelin'
Joined: Jun 2018
Posts: 1,477
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From: NJ, USA
I would put it back together and start it too.
Its either start it or tear down the motor and replace something that’s broken anyway.
The chance of catastrophic failure at idle is low. It was just running at idle to take the video.
Its either start it or tear down the motor and replace something that’s broken anyway.
The chance of catastrophic failure at idle is low. It was just running at idle to take the video.
Last edited by rtl5009; Jan 1, 2019 at 12:54 AM.
Three Wheelin'
Joined: Nov 2018
Posts: 1,269
Likes: 402
OP, this thread is certainly getting a lot of attention. I'm sure you're concerned about the outcome. My opinion again is that you don't have internal engine failure. I'm not a professional technician, just an average DIYer/enthusiast like many here. Here's how I see it:
1. Initial concern was a loud knocking sound, as you showed in initial video. Check Engine Light not activated.
2. You had two prior UOAs, each showing no concerns.
3. Filter had some ferrous particles. Dropping pan reveals two pieces of plastic or sealant and one piece of metal. In your pictures the pan looks clean otherwise, as does the oil pump intake screen.
4. The serpentine belt tensioner has failed. I believe you said belt wasn't in good shape. You've ordered a replacement tensioner and prolly a belt too.
5. I think pending oil analysis is coming back clean. The particles you found are too big to be seen by standard analysis.
6. Only other thing I can think of before putting it back together is to pull the spark plugs and check cylinders with a borescope. Replace spark plugs if indicated.
Other that I'd put it back together and start it. Assuming it sounds normal I'd run it 300-500 miles and pull the oil filter and examine it.
1. Initial concern was a loud knocking sound, as you showed in initial video. Check Engine Light not activated.
2. You had two prior UOAs, each showing no concerns.
3. Filter had some ferrous particles. Dropping pan reveals two pieces of plastic or sealant and one piece of metal. In your pictures the pan looks clean otherwise, as does the oil pump intake screen.
4. The serpentine belt tensioner has failed. I believe you said belt wasn't in good shape. You've ordered a replacement tensioner and prolly a belt too.
5. I think pending oil analysis is coming back clean. The particles you found are too big to be seen by standard analysis.
6. Only other thing I can think of before putting it back together is to pull the spark plugs and check cylinders with a borescope. Replace spark plugs if indicated.
Other that I'd put it back together and start it. Assuming it sounds normal I'd run it 300-500 miles and pull the oil filter and examine it.
Pro
Joined: Apr 2003
Posts: 563
Likes: 7
From: PA
The belt tensioner could definitely be the cause of the awful sounds and what you found in the pan could have been there for a long time.
That said, it’s really difficult not to be concerned about the debris found in the filter, especially if you have checked it previously and it was clean.
I’d like to think that a uoa could identify a blown engine, but it may be a gut call on whether to drive it or tear it down.
I’m hoping for a good uoa and many more miles of happiness.
That said, it’s really difficult not to be concerned about the debris found in the filter, especially if you have checked it previously and it was clean.
I’d like to think that a uoa could identify a blown engine, but it may be a gut call on whether to drive it or tear it down.
I’m hoping for a good uoa and many more miles of happiness.
Rennlist Member
Joined: Apr 2018
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OP, kindly update when you know more / have replaced the tensioner. I’ve heard that slight tick on my engine and many other 997.2’s as well. Driven the car 1500 miles with no oil consumption or problem so I’ve been assuming it’s “charm” as Bruce in Philly calls it. I’ll check my belt tensioner first chance I get now that you have found a failing example at similar miles to mine. Just kindly don’t leave us hanging as many OP’s do with this sort of thing. Cheers!
Pro
Joined: Dec 2017
Posts: 657
Likes: 98
From: Arlington, Texas
Two things to keep in mind about "ticking" on the 997.2. Compression ratio has been raised to 12.5 to 1, and more importantly the fuel injector pressure is way higher, ranging from 40 to 120 bar. DFI injectors fire several times too in cycle, not just once per stroke on port fuel injection engines.