Hi everyone, so while doing my last oil change I noticed what looked like the "glitter of death" in my oil. So I decided to investigate and removed my oil pan. This is what I found.

Obviously bearing material so I started pulling the rod caps.
Starting with #3:

#2:

#1:

And #4:

None of them look too great but definitely not the culprit for the metal I found. More likely just suffered oil contamination as a byproduct of the metal circulating around.
Here's the main caps staring with the girdle farthest from the timing belt side:

Center main cap:

This thing is HAMMERED. And obviously the one that failed.
Girdle closest to timing belt:


None of what I find makes me very happy, but onward and upward. Looks like its time for a rebuild. I guess my question is what is the most probable cause of main bearing failure? Oil starvation? Oil contamination? Fuel wash? This motor has just over 100k on it and was stock for almost all of that. Basically I don't want to spend the money to do a rebuild only to have the same issues occur. Any input would be greatly appreciated.

Almost every stock4g I have taken apart had the center main journal beat up like that. No idea why.

bastarddsm said:

Almost every stock4g I have taken apart had the center main journal beat up like that. No idea why.

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Hmm interesting. I assume the engines you disassembled had failed and you mean that is the most common point of failure?

No they were still running, just wore out.

bastarddsm said:

Almost every stock4g I have taken apart had the center main journal beat up like that. No idea why.

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I run a higher clearance race bearing for my center main, regular kings for the other 4. Mainly to let more oil out into the thrust.

bastarddsm said:

No they were still running, just wore out.

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Gotcha. This one ran too. Pretty well actually (made 150psi of compression across the board). Anyway if I have the bores honed, crank polished, and everything hot tanked before assembly do you think I will be fine?

You have more metal in the pan than what is missing from the thrust main.

Look back up in your block and check out your Balance shaft bearings.

BogusSVO said:

You have more metal in the pan than what is missing from the thrust main.
Look back up in your block and check out your Balance shaft bearings.

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Wouldn't I need to remove the oil pump and pull the balance shafts partway out in order to actually inspect the bearings? Either way the motor is coming out and being disassembled

I found strange pieces of unknown metal in my oil pan too. I pulled and disassembled my engine and didn't find any bearings damaged like that though. I wonder if it's something else like casting flash as well as bearing material in yours.

Can't really tell from your pic, but last time I see something like that it was bearing material from the turbo.

ForcePower said:

Can't really tell from your pic, but last time I see something like that it was bearing material from the turbo.

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Its definitely from the center main bearing. There are literal chunks of metal missing.

Smilinjay said:

Its definitely from the center main bearing. There are literal chunks of metal missing.

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Ok. My phone wasn't showing your pics very clearly.

mercaholik said:

I found strange pieces of unknown metal in my oil pan too. I pulled and disassembled my engine and didn't find any bearings damaged like that though. I wonder if it's something else like casting flash as well as bearing material in yours.

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That could be aluminum powder from cam journal and oil pump gears making metal to metal contact with aluminum. Just my guess. Sorry to see this happen to you. I have sources for parts if you need help just pm me.

keltalon said:

That could be aluminum powder from cam journal and oil pump gears making metal to metal contact with aluminum. Just my guess. Sorry to see this happen to you. I have sources for parts if you need help just pm me.

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Thanks, I may take you up on that . Thanks for the replies everyone. Im going to start a thread in the newbie forum about what all I nee for a rebuild, so I can get my car back on the road asap.

Yes pulling the front case will be the proper way to truly tell.

But due to the size of the chunks, and the amount of it.

If the BS bearing failed, it should be evident just looking up in the block, you would have more chunks hanging out the edges of the bore.

Update: The engine is out and completely disassembled. The balance shaft bearings looked fine. The only bearing surface with major wear is the center main. Still trying to determine the cause of this failure. I briefly considered fuel wash from running very rich for a short time before the car was base tuned, but why would only one bearing be damaged? And for that matter, I assume the rings would be the first things to go (since they are the first thing that would be effected if fuel were mixing with the oil) but this motor made 150psi across the board and didn't consume any oil.

While its apart have the line hone checked in the block, and crankshaft runout.

donniekak said:

While its apart have the line hone checked in the block, and crankshaft runout.

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As of right now im considering 2 different routes.
Have the crank polished and block honed and hot tanked by a reputable machine shop. Assemble with wiseco non hd pistons and eagle or manley rods, and acl bearings.
Or, buy a bottom end from a local ad that was machined and assembled by the same reputable machine shop with wiseco pistons, eagle rods, and acl bearings. The guy selling it is asking $1500, which is a bit pricey imo. But would save me some time and potential error in assembly at the cost of a few hundred bucks.
I actually started a new thread on this topic.

the bearing that damaged, is up side down. Dont theThe holes in the bearing go in the block side, not the cap?.

taylork057 said:

the bearing that damaged, is up side down. Dont theThe holes in the bearing go in the block side, not the cap?.

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On the center main there is an oil groove so both the block side and cap side bearings have holes in them. I just double checked this on my new bearings.

thanks for clarifying!

Just how reputable is that machine shop there's a reason to disassemble the bottom end and check clearances over and over again especially the block and piston clearances cylinder taper roundness etc that comes within the territory of a rebuild. Not saying they're a bad choice but just saying more than one machine shop has been the reason of unexpected rebuilds or rebuilds just not holding up many of them failing within a few short miles or a few thousand miles but still way before the time there're supposed to considering the upgrade over the stock level components within the rotating assembly.

Make sure if you do go that route to disassemble and inspect all components it may be time consuming but well worth the time invested as a little more time here pays off big time later and way less of a headache in the long run

10's or bust said:

Make sure if you do go that route to disassemble and inspect all components it may be time consuming but well worth the time invested as a little more time here pays off big time later and way less of a headache in the long run

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I opted against buying that shortblock. Mainly because like you said, i dont know the history of that block and what specifically has (or hasnt) been done to it. I ended up getting my crank polished and taking the bores .020 over with wiseco 8.3:1's and eagle rods. Just got the rotating assembly back from being balanced and am going to assemble it this weekend.

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