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

[soundman98]

"it depends"

on who keeps records. who reports the records. who makes those records available to others. and who records/watches for available records.

sometimes oil changes are reported. others lose the entire front end while driving through a kindergarten class that makes national news, while it still doesn't end up in any official record.

i've seen a number of odometer differences cause red flags over the years i've tried using carfax for vehicle history reports. most of the time, it comes down to some department knucklehead listing a vehicle mileage at 35,050 one year, 38mi/383,490mi the next, and 42,350 the next.

my car was listed by dmv/emissions records as a 'ranger' for a year, which, if carfax picks up, ought to be interesting how they handle a vehicle model change partway through it's lifespan... frankly, it doesn't matter to me. i'm keeping the car, and if resale comes to the front of my mind when discussing a car, then it's not a car worth keeping around anyways.

[Blighty]

Originally Posted by NoHaveMSG

The engine is built in Subaru's plant. Doesn't matter if Toyota was involved in the design or not. It has nothing to do with design and everything to do with manufacturing procedure.

So what, you are happy for your Toyota not to get fixed if you have an issue, and happy for them to say - sorry we cant do anything because hey its a Subaru not our car? No, didn't think so. Arguing about what plant its on and the implications of what dude needs to go and adjust what setting is counter-productive.

I wouldn't even be completely sure that its a process issue, what if the design specified amount and application area for the sealant, or a specific type, and that wasn't correct. Its not like these companies use excess stuff for no reason - money means that its usually that they specify a type or amount that is of the least amount/quality possible.

[Varelco]

Originally Posted by Opie

I disagree with this...and until proven otherwise this entire "loose sealant blocked the oil screen" thought process.

On the new 2.4 engine, the pick up uses a 5 sided screenbox to ensure proper oil flow in case of a partial blockedge. You can see it in the pictures floating around...it's a box with sealant at the top, but the other 4 sides of passages are open and clean. Unlike the previous version pickup that had a circular screen at the bottom that could be completely clogged. The little bit of blockage shown, while not ideal, would not grenade an engine and would maintain proper oil pressure.

I'd bet there is something else "starving" the oil on the cars that have failed. Maybe oil not returning to the pan in high g loads, (ie; drifting, hard corners), maybe low factory oil fills, maybe faulty PVC systems, maybe faulty new oil pumps.......

With how the sealant is sucked into the top it makes me think most of the oil is sucked through that face of the strainer, it's got enough force to suck it up and get stuck in there, it's not falling back out when the engine is off. I think under normal driving conditions the oil pump can get enough through the other faces of the strainer, but under high loads it can't.

Originally Posted by clio

When I've seen engine manufacturing lines on Youtube the RTV is applied perfectly/precisely, by robotics. I don't know how Subaru tackle this but I'd be surprised if it were done manually.

I don't think the issue is positioning, it's likely to be the quantity of the RTV sealant used and the cure time. If the matting surfaces have too much sealant and its still too wet before they are pressed together it will push out the sides.

[Tcoat]

Originally Posted by Blighty

So what, you are happy for your Toyota not to get fixed if you have an issue, and happy for them to say - sorry we cant do anything because hey its a Subaru not our car? No, didn't think so. Arguing about what plant its on and the implications of what dude needs to go and adjust what setting is counter-productive.

I wouldn't even be completely sure that its a process issue, what if the design specified amount and application area for the sealant, or a specific type, and that wasn't correct. Its not like these companies use excess stuff for no reason - money means that its usually that they specify a type or amount that is of the least amount/quality possible.

Nobody is saying that Toyota should not be making their customers good if they have problems.
The engines are Subaru, designed by Subaru engineers, Made in Subaru plants by Subaru employees. The identification and fix of the ROOT CAUSE is a Subaru issue. This is why what plant is indeed very important. Remember that Toyota buys these cars from Subaru. They are customers just like you.

You counter your own statement at the end there. If they designed it for a certain amount and that amount is not what is there then it is a process issue.

[Tcoat]

Originally Posted by removedonut

The ECM in this car does not monitor oil pressure, nor is there an oil pressure sensor anywhere in the car. There is a simple switch that engages when there is absolutely zero oil pressure in the car. This requires A LOT to go wrong, and as mentioned you can have complete catastrophic engine failure without it ever coming on.

Like any car with an oil pressure idiot light by the time you see it it is usually to late!

[Tcoat]

Originally Posted by soundman98

what i believe you're looking for is 'diminished value', ie; with the recorded change of the motor, there's a loss of the resale value of the vehicle when compared to the same vehicle without the manufacturing defect that caused the replacement.

i believe that's an entirely separate legal proceeding that you would pursue through typical legal channels against the automaker after the work was performed and noted on the vehicles history.

Diminished value is an insurance thing and not appliacble to break down of mechanical parts.
It is simply the difference between market and actual value of a car that has been repaired due to an accident.
Even then there are very specific requirements as to who and what caused the accident and can only be claimed if you are not at fault.
Replacement of a blown engine either through warranty or privately is not an accident. So... unless your damage is caused by an accident with blame on somebody else there is simply no way to claim diminished value.

[OkieSnuffBox]

Originally Posted by Tcoat

You counter your own statement at the end there. If they designed it for a certain amount and that amount is not what is there then it is a process issue.

Beat me to it.

This person is obviously not familiar with "manufacturing engineering."

[Tcoat]

Originally Posted by OkieSnuffBox

Beat me to it.

This person is obviously not familiar with "manufacturing engineering."

Over the years he has proven to be unfamiliar with many things but still has strong opinions on them.

[NoHaveMSG]

Originally Posted by Blighty

So what, you are happy for your Toyota not to get fixed if you have an issue, and happy for them to say - sorry we cant do anything because hey its a Subaru not our car? No, didn't think so. Arguing about what plant its on and the implications of what dude needs to go and adjust what setting is counter-productive.

I wouldn't even be completely sure that its a process issue, what if the design specified amount and application area for the sealant, or a specific type, and that wasn't correct. Its not like these companies use excess stuff for no reason - money means that its usually that they specify a type or amount that is of the least amount/quality possible.

Changing the argument is not a valid tactic.

The specified sealant, amount, and application area is very well known and understood since it has been in use for a decade on the same family of engines. If that was the issue we would be seeing it on a lot more engines now wouldn’t we?

[Petah78]

LOL....the internet is certainly having some fun about this.

[WolfpackS2k]

Oil pressure switches (as found on many vehicles) are 100% worthless. My Cayman had an oil pressure switch, and was good enough to tell me I had zero oil pressure when I tried to restart the engine, AFTER I had already lost the #6 cylinder rod bearings from oil starvation. It's basically a feature to tell you you're already f*cked.

If someone intends to track their car on a regular basis, I would highly recommend installation of an oil pressure sensor and real time display gauge.

[DocWalt]

Originally Posted by Tcoat

It MAY have already caused damage. There is no way to know without pulling the whole engine apart or it completely fails.
Just because there is RTV it does automatically mean damage was done. If severely blocked the damage will usually be immediate and catastrophic.
Besides, the point was that a baffle plate is not a solution since if indeed blocked enough to cause damage adding a baffle plate won't reverse that and if no damage had yet occurred then removing the blockage prevents it.

Correct, it MAY have caused damage. If Subaru/Toyota are smart they won't take that risk and they'll replace the engine in entirety.

[DocWalt]

Originally Posted by Opie

I disagree with this...and until proven otherwise this entire "loose sealant blocked the oil screen" thought process.

On the new 2.4 engine, the pick up uses a 5 sided screenbox to ensure proper oil flow in case of a partial blockedge. You can see it in the pictures floating around...it's a box with sealant at the top, but the other 4 sides of passages are open and clean. Unlike the previous version pickup that had a circular screen at the bottom that could be completely clogged. The little bit of blockage shown, while not ideal, would not grenade an engine and would maintain proper oil pressure.

I'd bet there is something else "starving" the oil on the cars that have failed. Maybe oil not returning to the pan in high g loads, (ie; drifting, hard corners), maybe low factory oil fills, maybe faulty PVC systems, maybe faulty new oil pumps.......

Originally Posted by ninjan00dles

Cavitation due to inlet blockage... you have to take into account mass flow rate, fluid velocity as the suction inlet shrinks, oil pump speed /rpm and a few other things. If you have a blockage the fluid velocity has to increase to maintain the same mass flow rate which lowers your pressure, look at bernoulli's law. Even if it's not completely blocked, at sustained high RPM with all those factors that's enough to give you enough starvation to spin your bearings.

There was a guy who tracked extensively /owned a shop in South America (Peru?) on this forum who was blowing 13-16 motors left and right until he went to a larger pickup tube. The thread should be on this site, he had some good data points.

So much of what ninja said.

Sure it's still getting flow from the other 4 sides but it's not getting *proper* flow.

This is a fairly basic engineering problem and anyone that's saying the RTV isn't causing the issue is simply not understanding how much little things matter. If Subaru/Toyota thought they didn't need that side of the box to be open, they'd have left it closed.

[Robertw]

Originally Posted by Petah78

LOL....the internet is certainly having some fun about this.

Curious if Toyota or Subaru even care about the media shit storm regarding this issue, or if it even matters to their bottom line.