Think a got a Rod Bearing going South

[Mitch1]

Well, crap. Changed the oil at 300 and 600 miles. Changed it again today at 750. At all three changes oil from case looks like metallic paint. At first I thought it was normal break-in shmultz, rings seating and stuff like that. I though it would probably, or hopefully dissipate over the next change or 2. Looks the same. Decided to drop the sump screen and check, while crossing my fingers. Sump screen is clean. So it hasn't spun yet? Any advice on how to proceed? Drive and look for more symptoms? Oil pressure is good. About 1.5 bar at idle with 20w-50. I have drilled out cam spray bar adapters. Good pressure throughout rpm range. No abnormal noises. Sucks.

[cgarr]

Are you getting a noise from the bottom end? Is there a reason your rod bearings would be going bad this quick? The glitter in the oil is not uncommon this early even with oil changes, you never get all the oil out and it looks worse than it really is, in other words it does not take much to make the oil look like this.

If all the pressure readings and sounds good, with a clean sump I would drive it. Normally I dont change it that early or often but I know others do.

[Lapkritis]

How thorough are your changes? Front Mount cooler and lines flushed clean?

I would send a sample of oil in for analysis. They can tell you what is in suspension.

[Mitch1]

Thanks Craig and Lap.
@Craig. No. No noise from bottom end like rod knock. That's pretty distinctive and even a novice like me can probably hear that. It runs and sounds good. I just think I might be seeing early signs of bearing failure. One of the things I keep thinking about is how much that SAE 30w flows at temp. When draining from tank and case when hot it flows like water. Which makes e wonder. I never took the engine over 5k, but I did rock it from 2k to 5k in 3rd and 4th on a few drives to help seat rings. Good news I think rings are seated. Bad news I made have damaged a bearing.

@Lapkritis. I don't flush the oil lines or trombone. I might on the next one though.

[Lapkritis]

For break-in, I personally run nothing thinner than 10w.

[brighton911]

Hi John. I saw your earlier post about using 30w for break-in oil and now this. I too used 30 as a starting point and had no issues. Sure, when hot, it thins out big time but that's normal for most oils. And the shinys are also fairly normal too. It does seem strange you are seeing it through so many oil changes. I changed mine once at 500 miles with not much to be seen. I considered it broken in at that mileage, rings were fully seated by lots of on and off throttle and no steady speeds.
You mentioned rings are seated, what cylinders do you have? I think if you had a rod bearing going, you wouldn't have to wait very long for the noise to appear and it would seem you should be way past that time. And the fact your oil pressure at idle is that good speaks positive for the bearings being fine. If you are still concerned and as suggested, why not send your oil off for analysis, that will tell the full story. I think /hope you may be worrying for nothing. For sure, failure like that would be a day spoiler. Good luck.

[Mitch1]

Thanks for he reply Brighton.
Yeah, I think if it is I'll know sure enough pretty soon. The cylinders are re-ringed alusils. Some of the sparkle dust is magnetic. Could be rings seating against the silica of cylinder walls. My other thought is chains. The chains are new and the sprockets on the intermediate shaft are new. Sprockets at cam I re-used because they looked good. Maybe sprocket or chain wear? Intermediate shaft bearing?

[Mitch1]

Went out and wiped out pan and added some mineral spirits. Some of the specks do appear to be copper colored. Not good.

[cgarr]

What was done when you rebuilt this motor? and why did you rebuild it? did it suffer a catastrophic failure before rebuild? everything cleaned out real good during rebuild? Might wan to cut the oil filter open and have a look too?

[Mitch1]

Craig,
No catastrophic failure. Just oil leak fixes that went too far. Re-ringed alusils. Crank inspected and micro polished by Ollies. Rods resized at Ollies. New bearings. All oil galleys in case and crank cleaned at Ollies. p&c's inspected and cleaned. You did rockers and shafts. John did cams. Case was vat'd at Ollie's.
Making good oil pressure. Gotta feel like if any bearing was opening up I'd see the drop on oil pressure? Maybe I can't hear the knock. Yeah. Going to drop the filter from last change at Zims and see if they have a filter cutter.

[Mitch1]

Craig,
No catastrophic failure. Just oil leak fixes that went too far. Re-ringed alusils. Crank inspected and micro polished by Ollies. Rods resized at Ollies. New bearings. All oil galleys in case and crank cleaned at Ollies. p&c's inspected and cleaned. You did rockers and shafts. John did cams. Case was vat'd at Ollie's.
Making good oil pressure. Gotta feel like if any bearing was opening up I'd see the drop on oil pressure? Maybe I can't hear the knock. Yeah. Going to drop the filter from last change at Zims and see if they have a filter cutter.

[Mitch1]

I removed the sump plate yesterday to check screen. Nothing there.

[Lapkritis]

Do you have magnetic drain plugs? Wondering how much you have deposited on those... at this point I think you're on the right track for a couple consecutive oil analyses. You'll be able to confirm wear once you have a benchmark reading - anything way out of whack will also show on the initial report.

[Mitch1]

Yeah, on all changes nothing really on drain plugs. I wanted to check yesterday with oil really hot. So as soon as I parked it in garage I got out and started draining oil. Dropped the case plug in pan so I didn't get a good look at it right out of case. But it was pretty clean. I'll continue to drive it easy keeping an eye and ear out. Maybe get a Pro to drive it and listen next week. Change the oil on next go around at another 250 to 300 miles if nothing has changed when driving it and send a sample off. I'll check the last filter tomorrow and report back.
Interesting now with 20w-50 in it the exhaust smell is gone. Was using 30w nd with zinc additve and the exhaust really smelled a while after shut down.

[Mitch1]

Spoke with Mayo's today. Cut open last filter. It was clean. How do I have stuff from case, but not in filter? Tom said most likely chain material. Advised to drive another 500 miles and change again. We'll see.

[stownsen914]

How well did you clean out the crank after having it polished? Years ago when I did the motor in my 914/6 racecar, I was astounded at how much fine metal crap came out of the crank when I flushed the oil galleys for HOURS in a parts washer. I could imagine that stuff coming out in oil changes like yo u describe ...

[Mitch1]

Ollie's removed crank plugs and cleaned. But I also shot brake clean through each journal passage when i got it. Probably used 2 cans.

[KTL]

If a bearing was coming apart it doesn't tease you and do it slowly. Once the failure has occurred it goes all the way. If your drain plugs look good and your filter looks good, i'd stop worrying and move on.

If your drain plugs and sump plate looked like this, you should be concerned.

[Lapkritis]

^Disagree, respectfully.

Occasionally, rod bearing wear may be observed well prior to failure. Although more common in vehicles tuned incorrectly, it can happen gradually in all. The Mitsubishi 4G63 is notorious for this... as are other turbo engines where extreme loads on the bearings can cause gradual erosion. In engines where they are more frequently worn, the community simply accepts the practice of regular replacement. During visual inspection, a tired bearing is obvious. More seasoned veterans can pick up the sound which leads often to inspection of the oil/filter. I've done this myself in the past on numerous occasions with various engines.

[cgarr]

Well If the bearing is going bad after only 700 miles that's not very gradual I would think: