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Discussion Starter #1
I was at the Ridge Motorsports Park the other weekend when this happened to me:

https://www.youtube.com/watch?v=jgvrab97spI

After getting it towed home, I pulled the valve cover and oil pan. I found some metal in the oil pan (see the attached picture). I could not see any damage inside the bellhousing after removing the inspection cover.

So far I think that something let loose in the valve-train. My next step is to pull the head and inspect further unless someone has a similar experience that points to something else.
 

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Spun a bearing is my guess.

EDIT: pretty easy to pull the rod cap ends off and look at the bearings with just the pan off ... I'd start there before you pull the head.
 

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If the crank is not damaged (looking for blue hot spots and surface irregularities) then you can probably just replace the bearings (using plastigage to determine bearing type) and rod cap bolts.

Debris that large will not make it to the oil pump. But you'll just need to evaluate visually -- you maybe lucky, you may not.
 

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Discussion Starter #4
I didn't think it was a rod bearing at first because of the "faster" nature of the noise. Also, the piece I found in the oil pan didn't look like bearing material. Other engines I have built or worked on had bearings that were more bronze in appearance. I saw a couple other pieces in the oil pan, all smaller. Nothing caught in the oil pick up.

Should I have an oil sample evaluated if it is a bearing? I'm concerned about material in the journals and oil coolers.
 

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Watched vid. Assuming that you just didn't have the muffler pop off the head pipe;), sounds like intake noise. These motors are not too common to spin bearings. They are common to drop intake valves. They are also common to break ring lands, even in NA motors, from fuel starve. Everyone puts an oil pan on the car when the most common motor destruction is fuel starve, not oil starve... anyway...

Pull your plugs. If a plug is scrap you know it's new motor time and you broke a ring land and/or a dropped valve destroyed the pistons, etc...That's also where the metal came from.

If the plugs look OK, that's good for the rotating group. next do compression test. Chances are that one will be 0. Next, shine a light down the 0 hole. You will probably see an intake valve shrouding the plug hole. Pretty standard deal if this is the case. You will need to rework the head in this case, as the corresponding valve guide will be broken and need replaced. You'll replace all the valves with ferrea units if you're smart;) Also change out the springs for Eibach or ferrea and the problem will not happen again.

Hope that helps,

Phil
 

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Not sure what oil evaluation will do at this point? You indicated you didn't see any problems with the valve train after removing the valve cover. When one of my stock valves let go it didn't sound anything like your video.

Can you expand on what other diagnostics you've done? Checked plugs?

Will the motor turn over (without starting - hand crank it without spark plugs in). If so, have you compression tested?

Good to be concerned about debris in the journals -- typically you toss/replace oil coolers after any major debris damage (you can sonic clean but I'm not confident in that process) -- if you are running OEM 27 ft of stock oil cooler line that will be difficult to flush.

Another thing to check is your squirters, are they all still there?

EDIT: Based on where this happened in your video it does look like it would be oil pressure or fuel pressure related.
 

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Discussion Starter #7
I pulled the plugs and inspected all the cylinders visually. Everything appeared normal, except there was some oil in the #1 plug well. It appeared to be a slow leak from the valve cover. The tips of all the plugs were good and the same condition. The engine will turn over, but I have not done a compression check yet. I did not check the squiters. The camshaft lobes all looked like they were in the same condition. I kinda assumed the oil analysis wouldn't tell me anything I won't find out otherwise, but I thought I'd ask.

So I'm leaning towards a spun rod bearing at this point.
 

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Meant to say "does NOT look like it would be oil pressure or fuel pressure related" ... meaning no heavy or extended G loads at the point of failure.

Yeah, oil in plug well probably means leaky valve cover seal, cheap and easy to replace.

If it is a spun bearing be careful with turning the motor over as it could add further damage to the crank. Pulling the rod caps off is really easy and I know you're not supposed to re-use the bolts but I have before without any issues, but new bolts and bearings are only about $100 and the recommend way (just be sure to note bearing order and top/bottom in case that isn't the problem and you need to put them back).

Rob
 

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Discussion Starter #9
As far as fuel goes, I had over half a tank of fuel when the failure occurred. I have ran it low before and experienced fuel starvation, but I usually avoid it.

I'll check the bearings and compression next.

I've done the re-use bolts thing before too. I don't have as much of a problem with the cost as sourcing them. Though I've also never had problems re-using them.
 

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Discussion Starter #10
I didn't pull the bearing caps yet, but the compression test was 215 225 220 220. Doesn't seem to be the top end. No knocking sounds during the compression test.

Could it be the clutch? I didn't notice a change in feel or vibration when pressing the clutch pedal. Kinda stumped.
 

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Discussion Starter #11
I forgot to mention that the piece of material that was in the oil pan is not magnetic. It is also only 0.012" thick. Could it be left over from machining the engine?

The oil does not look like there was catastrophic damage to the engine or bearing. There is not a large amount of debris in the oil or oil pick-up like I have seen on another engine that I spun a bearing on. :confused:
 

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FYI, compression can test out fine with a spun bearing.

Watched the video again, looks like it rev'd fine after your initial issue. The sound was proportional to engine rev's so it's not axle/transmission ... could be clutch/flywheel. I'd still check the rod bearings, but if they look fine, then button it back up, add oil and see if it starts and idles.
 

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...The sound was proportional to engine rev's so it's not axle/transmission ... could be clutch/flywheel...
+1

The video sounded a lot like my clutch exploding and attempting to machine its way out of the bellhousing a few weeks ago at Buttonwillow.
 

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I can tell you what the alloy is within a couple percent if you send a piece to me. The test is nondestructive and I can send the piece back. I have an SEM with EDX spectrometer. PM me if interested.
 

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Discussion Starter #15
UPDATE

Well, with the car in storage and the holidays here, I'm finally taking the time to update this thread.

I was able to have the piece of mystery metal analyzed by wdonavan and all that was reviled was that the material was generic aluminum, such as block or head material with machining marks on it. So the good news is that there appears to be no real damage to the engine, the bad is that I (and I suppose others may) have an engine that from the factory had little bits left in it. Not a fine example of quality control.

Once the car was up on the lift, I was able to get a much better view through the clutch inspection cover. There was some light scaring in the bell-housing and what appears to be a piece of the diaphragm spring laying in the bottom between the flywheel and bell-housing. I haven't removed the clutch yet, and probably won't for months, but it's safe to say that's what broke.

So I'm taking recommendations for a replacement clutch. My goals are reliability on the track, street ability and cost, in that order. I will be staying with stock NA power for the foreseeable future. I'm leaning towards the ACT HDSS right now.
 

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Well, with the car in storage and the holidays here, I'm finally taking the time to update this thread.

I was able to have the piece of mystery metal analyzed by wdonavan and all that was reviled was that the material was generic aluminum, such as block or head material with machining marks on it. So the good news is that there appears to be no real damage to the engine, the bad is that I (and I suppose others may) have an engine that from the factory had little bits left in it. Not a fine example of quality control.

Once the car was up on the lift, I was able to get a much better view through the clutch inspection cover. There was some light scaring in the bell-housing and what appears to be a piece of the diaphragm spring laying in the bottom between the flywheel and bell-housing. I haven't removed the clutch yet, and probably won't for months, but it's safe to say that's what broke.

So I'm taking recommendations for a replacement clutch. My goals are reliability on the track, street ability and cost, in that order. I will be staying with stock NA power for the foreseeable future. I'm leaning towards the ACT HDSS right now.
I've got a Fidanza in good shape, I'll let it go for a song. Pm if interested.
 

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Bringing back this old thread since it seems my clutch exploded yesterday on track.
I was going down the front straight at PIR in 5th gear when suddenly the engine sounded like a coffee grinder, exactly the same noise as in the video from the OP.
Coasted into the short shoot of the chicane and parked the car there until the session was over and they could tow me back into the pits.
First guess was that something at the top end of the engine let go.
But when we unloaded the car from the tow truck at home I noticed the clutch inspection cover was hanging out of one of the air ducts:

IMG_0662.jpg

I can't see anything suspicious when looking in the inspection opening, but when I manually turn the engine it spins freely in some spots and then gets stuck.
When I forcefully turn it further I hear a grinding noise coming from the clutch area.

I guess it's time for a clutch upgrade

I'll still pull the plugs and the valve cover to confirm the engine is not the culprit.

Does anyone have any other idea what to check first before I start pulling the transmission?
 

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Bringing back this old thread since it seems my clutch exploded yesterday on track.
I was going down the front straight at PIR in 5th gear when suddenly the engine sounded like a coffee grinder, exactly the same noise as in the video from the OP.
Coasted into the short shoot of the chicane and parked the car there until the session was over and they could tow me back into the pits.
First guess was that something at the top end of the engine let go.
But when we unloaded the car from the tow truck at home I noticed the clutch inspection cover was hanging out of one of the air ducts:

View attachment 698345

I can't see anything suspicious when looking in the inspection opening, but when I manually turn the engine it spins freely in some spots and then gets stuck.
When I forcefully turn it further I hear a grinding noise coming from the clutch area.

I guess it's time for a clutch upgrade

I'll still pull the plugs and the valve cover to confirm the engine is not the culprit.

Does anyone have any other idea what to check first before I start pulling the transmission?
I had basically the same sound when my clutch exploded on the track too. I could not see anything odd in inspection port, which is surprising since I got all kinds of shrapnel out when the transmission was off. In fact, it damaged the bell housing. Getting that replaced was an adventure. Hope the motor is OK and you get a nice new clutch.
 

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What's that old saying: Advice is something we often ask for when we know the answer and wish we didn't...

It's the clutch;)

Fortunately it's not a terrible job especially with a clamhinge:D

Swap for the Fidanza FW and bolts when apart. It's a welcomed upgrade. We've got all that you need on our site, FWIW.

The trans removal process is well documented on this forum as I'm sure you've found. Happy to help if you hit a road block though. We do a lot of them...

Good luck,

Phil
 

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Thanks guys :up:

Here's the video of the last lap when it happened


Somehow I would have expected the clutch to let go during a shift and not while in 5th gear casually cruising down the straight :confused::D

Phil, you are incorrect with your saying that the clutch is not what I wanted to hear. I'm actually hoping it's the clutch and not a dropped valve or broken rocker. I much rather change the clutch and maybe the flywheel (hopefully not the bell housing) than the engine. Trying to fix the engine and get metal shavings out of the oil coolers and lines sounds neither easy nor cheap :rolleyes:

And yes, I have all the documents for the removal process printed out and sitting on my workbench in the garage, ready to go.

Maybe I'm strange but I was kind of getting bored with just changing fluids, brakes and tires and I'm looking forward to finally have something to wrench on again :D

I'll probably take Friday off and drop the transmission. Once I have a better picture of the carnage I'll give you a call Phil!
 
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