Potential Cause of rumored GR86’s blown engine? Seal packing(RTV) was peeled off

[OkieSnuffBox]

Originally Posted by Petah78

My theory is that this can be a sudden or a gradual death, and in the event of a gradual problem, UOA will pick it up.

That's a bit like saying the answer is Yes or No.

That's exactly the point of UOA. That's why Blackstone Labs has been around for almost 4 decades. Incredibly popular in the BMW crowd who have cars with S motors known for eating rod bearings.

Engines like the S54 in the E46 M3 are notorious for this. Some speculation is that bearings are too narrow to carry the HP and RPM load of the engine, since it has the same bore spacing as the old M20. A 6k 170hp engine, not an 8400rpm 333hp engine.

Some of the pro's think the reason is guys beating on the cars before the oil is fully up to temp.

Originally Posted by Tcoat

Agree there is a lack of info on other bearings since most find the one and "OK there is the problem we are done here" but there have been enough saying just the one that I am comfortable in making the statement.
If there was even one oil analysis that said "we have concerns" I may also change my outlook but there just isn't.

Failure mode and risk analysis of industrial processes are what I have done for 30 years and I will say that with what we have I am about 75% confident that these failures are sudden. I would be happy to change that level (up or down) with a nice big data set but I don't think we are going to get much more info than we already have. Really the only new data I expect is if the mileages go up and there are still multiple failures but at this point they seem to have stopped. Or at least no longer get reported!

I'm more curious about build dates, so far it seems most of the ones reported have been 11-12/21 build dates.

[Tcoat]

Originally Posted by OkieSnuffBox

That's a bit like saying the answer is Yes or No.

That's exactly the point of UOA. That's why Blackstone Labs has been around for almost 4 decades. Incredibly popular in the BMW crowd who have cars with S motors known for eating rod bearings.

Engines like the S54 in the E46 M3 are notorious for this. Some speculation is that bearings are too narrow to carry the HP and RPM load of the engine, since it has the same bore spacing as the old M20. A 6k 170hp engine, not an 8400rpm 333hp engine.

Some of the pro's think the reason is guys beating on the cars before the oil is fully up to temp.



I'm more curious about build dates, so far it seems most of the ones reported have been 11-12/21 build dates.

That is why I am watching the oil results so closely. So far there is zero indication of gradual abnormal wear. That could of course change with more results but still looks sudden.

I never really looked at dates since I was looking more for a failure mode than anything. I would guess that it is probably a pretty tight range though. These things usually don't last long before they are caught.

[OkieSnuffBox]

Originally Posted by Tcoat

That is why I am watching the oil results so closely. So far there is zero indication of gradual abnormal wear. That could of course change with more results but still looks sudden.

I never really looked at dates since I was looking more for a failure mode than anything. I would guess that it is probably a pretty tight range though. These things usually don't last long before they are caught.

I've been curious about the build dates because, the dates seem clustered. So maybe a bad batch of RTV? Machine out of calibration? Etc.

[justinco]

Originally Posted by Petah78

....

And some additional info, pretty sure he is a member on here....

That's me, and here is the report from the video:

[Petah78]

Originally Posted by OkieSnuffBox

That's a bit like saying the answer is Yes or No.

That's exactly the point of UOA. That's why Blackstone Labs has been around for almost 4 decades. Incredibly popular in the BMW crowd who have cars with S motors known for eating rod bearings.

Engines like the S54 in the E46 M3 are notorious for this. Some speculation is that bearings are too narrow to carry the HP and RPM load of the engine, since it has the same bore spacing as the old M20. A 6k 170hp engine, not an 8400rpm 333hp engine.

Some of the pro's think the reason is guys beating on the cars before the oil is fully up to temp.



I'm more curious about build dates, so far it seems most of the ones reported have been 11-12/21 build dates.

Yeah, I am just not ruling anything out. I just feel that UOA can provide some cheap insurance, though cannot completely eliminate the problem.

Build dates are definitely interesting. I don’t think there is an established pattern for RTV. And I don’t think there are enough samples with engines failures to establish a pattern?

[Tcoat]

Originally Posted by Petah78

Yeah, I am just not ruling anything out. I just feel that UOA can provide some cheap insurance, though cannot completely eliminate the problem.

Build dates are definitely interesting. I don’t think there is an established pattern for RTV. And I don’t think there are enough samples with engines failures to establish a pattern?

Oh there is a pattern. Yes it could be better with more data but still a pattern.

The oil analysis is great but by the time you get the results telling you there is an issue the damage is already going to be done.
Justin's report is almost perfect much the same as all the rest. There is just no evidence at all (at this point) that there is any gradual wear happening.

[Petah78]

Originally Posted by Tcoat

Oh there is a pattern. Yes it could be better with more data but still a pattern.

The oil analysis is great but by the time you get the results telling you there is an issue the damage is already going to be done.
Justin's report is almost perfect much the same as all the rest. There is just no evidence at all (at this point) that there is any gradual wear happening.

What is the pattern you are seeing? RTV or failures?

Problem is that we have not seen any UOA of the failed engines while it was still running (or again, maybe i missed this info?) thus we do not know if they were suffering from a gradual slow death. All the positive UOAs that we have seen thus far are from engines that have not failed and very well might never fail. What i am seeing is that more evidence suggests that RTV is not causing premature wear so these spun bearings is likely not related.

[Tokay444]

Originally Posted by Tcoat

Oh there is a pattern. Yes it could be better with more data but still a pattern.

The oil analysis is great but by the time you get the results telling you there is an issue the damage is already going to be done.
Justin's report is almost perfect much the same as all the rest. There is just no evidence at all (at this point) that there is any gradual wear happening.

The only way for there to be no gradual wear is to never start the engine.

[Tcoat]

Originally Posted by Tokay444

The only way for there to be no gradual wear is to never start the engine.

True. The better term would be abnormal gradual wear.
Never starting the engine brings up a whole different set of issue though.

[Tokay444]

Agreed.

[Tcoat]

Originally Posted by Petah78

What is the pattern you are seeing? RTV or failures?

Problem is that we have not seen any UOA of the failed engines while it was still running (or again, maybe i missed this info?) thus we do not know if they were suffering from a gradual slow death. All the positive UOAs that we have seen thus far are from engines that have not failed and very well might never fail. What i am seeing is that more evidence suggests that RTV is not causing premature wear so these spun bearings is likely not related.

As I have said many times there is more than just the obvious collected RTV at play here. Everybody is fixated on that because it is so in your face that they tend to miss the bigger picture.

The failed engines to this point have all been very low mileage and abnormal gradual wear to the point of bearing failure just does not make sense. I bet that any analysis on those engines minutes before they failed would have shown no problem.

Bearings most often spin due to poor lubrication. There are of course other things that can come into play but lube is by far the number one cause. This is not a new or even uncommon issue. Usually means that somebody didn't watch their oil level though. When just one bearing spins and the rest are fine (as we know from a couple of examples) that means the flow was impeded to that one bearing. There have been enough examples of small pieces found in the oil filters to know that at least some made it into the system. A piece not much bigger than the head of a pin blocking a bearing oil journal is more than enough to take out that single bearing very quickly. Add the stress of performance driving to that reduced oil flow and the result is sudden and catastrophic failure.

[Robertw]

Originally Posted by Tcoat

As I have said many times there is more than just the obvious collected RTV at play here. Everybody is fixated on that because it is so in your face that they tend to miss the bigger picture.

The failed engines to this point have all been very low mileage and abnormal gradual wear to the point of bearing failure just does not make sense. I bet that any analysis on those engines minutes before they failed would have shown no problem.

Bearings most often spin due to poor lubrication. There are of course other things that can come into play but lube is by far the number one cause. This is not a new or even uncommon issue. Usually means that somebody didn't watch their oil level though. When just one bearing spins and the rest are fine (as we know from a couple of examples) that means the flow was impeded to that one bearing. There have been enough examples of small pieces found in the oil filters to know that at least some made it into the system. A piece not much bigger than the head of a pin blocking a bearing oil journal is more than enough to take out that single bearing very quickly. Add the stress of performance driving to that reduced oil flow and the result is sudden and catastrophic failure.

How would the rtv be getting through the filter? Aren't most filters capturing particulates at the 30-40 micron level?

[Tcoat]

Originally Posted by Robertw

How would the rtv be getting through the filter? Aren't most filters capturing particulates at the 30-40 micron level?

It can be introduced after the filter since many parts use it. There are several different colours involved not just the grey from the pan and the timing cover.
The oil filter is bypassed on cold start and under high pressure. Not every ounce of oil goes through the filter all the time.

The big stuff caught in the pickup is the least of the worries as far as I see.

[dreamwonder]

Originally Posted by dreamwonder

Will add a data point. Mine was built on Oct/21, have 12k miles on it so far with about 3 to 4k of that in DE. No issues so far.

Spoke too soon. Guess my number is up.

Toyota denied warranty. Goodwill denied as well.
Reason:
1. Previous gen oil filter was used.
2. 0w30 oil was used.
3. Car hit 129mph at 8300rpm on 5th gear ???

Car saw 32 days with 14k total miles before engine failed. If I was at fault, I will own up to it. But wow...this is my 3rd 86 and have hundreds of days on previous 2 cars.