We're getting somewhere ...
 

Let's start off with a picture. Tell me what's wrong with this picture. (Hint: running DISI motor, look at the oil rings)

Exhibit #2 ... the result of oil ring failure and fuel washing down the cylinder wall. (zoom in to the full size)

BTW, this is worse than a Honda with 200k on the clock.

the oil control ring "holes" are caked with oil.

i thought you said it had nothing to do with the oil control rings? ive suspected those since i pulled my stock motor apart.

And solution?

just for a noob.. can you link a picture as to what would be more normal or acceptable? TIA

Not sure there's really any solution to this other than port injection. Are any of the other DI motors in the world suffering from this? Aside from using a heavier weight oil, is there a solution? Can we use the AP to lean up idle? Do low fuel pressures due to shitty pumps attribute to poor atomization of the fuel causing the wash down? To me, it's just a shitty engine design. Sometimes this stuff is trial and error and Mazda just didn't get it right. I just don't know how else you could prevent this without modifying the injection system or getting rid of the DI altogether.

lex if u wanna spill the beans dude go ahead just make sure u give credit where its due (and im not talking about me lol)

Lex, i know you were up late last night but wake the fuck up and start explaining :) :)

Miles on the motor, compression, modifications, general pattern of treatment, used oil analysis? Too many variables to draw any conclusions without further data.

Based on what I see, I'd recommend everyone go to a 10 weight oil, change it often and cut back on the short trips but, still, too little evidence to draw a meaningful conclusion from.

fuel is washing down the cylinder causing excessive heat which could lead to the piston seizing in the cylinder thus bending or breaking the rod

There are many things going on here. It's really a path of discovery with this motor and many have helped along the way and yes I have tried some dead end roads. If you follow a lot of the discussions on blown motors it will steer you in the right path.

Yes, oil control rings are caked. No, I don't think there's much you can do to prevent the situation . Yes, I think it's a problem for the longevity of the motor.

I will let more people chime in here before I go any further. However, the issues we have seen on this platform and motor are all related.

heres your first hint

http://www.mazdaspeedforums.org/foru...-cursed-15469/

maybe that is one of the reasons dcr "corrected" the forged pistons going into jumpingjacksons whip. u can see how they flattened out the top of the piston.

http://www.mazdaspeedforums.org/foru...e-build-37856/

I don't think it has anything to do with the squish region.

why would dcr do that in the first place? my guess is that it helps distribute the pressure after detonation which equals less stress on the piston/rod and all the little components aka Seals and shit. tell me if im wrong, does anyone know why that is beneficial?

darrell speaking on piston correction

DCR Machine Shop Services... - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum

I guess this part of the process could help. I didn't know he was doing this. But the rest of it probably wouldn't help much for our issues.

One of the root causes of the issue here is fuel impingement. Who the fuck designs an injector that sprays at the cylinder wall??

Diesels have it too. But diesels have the injector at the top of the cylinder and have a dish to disperse the fuel away from the cylinder wall.

I honestly don't think ANY of us are immune to oil control rings failing, carbon buildup on the ring lands, and likely piston seizure.

Jon at PTP has said this before. On top of this, look at the piston crowns. The fuel spray is cooling parts of the piston unevenly causing hot spots and perhaps weakening the material.

Throw in a little detonation due to oil now entering the combustion chamber and lowering octane, more boost, carbon buildup, and a closed/open loop transition and you have a recipe for a seized piston. That then takes out the rod. Nothing to do with weak rods here.

It's not a coincidence you see knock after a lot of highway cruising. It's not a coincidence the car commands more fuel when knock is encountered.

Does the oil consumption issue now make sense? Thestaplegunkid said he had oil burning 4 days before it blew.

Finally, take a look at the bore where he blew the motor. Look at the scuffing. Look at the mark on the bore. That's where the piston seized, it cracked, and the carnage proceeded.

I have to say this is hands down the best information I have seen on this issue. Great work dude, keep it up.

AAAAAAAAAAAAAANNNDDD the shit has hit the fan.

see you guys in the FS section lol

fuck my couch.

safe to say that my car is staying stock and being sold before that drivetrain warranty is up

Evo be in my driveway within the next 2 months. I will make sure of that... somehow someway.

I concur.

Good work Lex, keep the information coming.

Lex, I would like to thank you for all the time you are putting into figuring out the problem with the engine.

But, you are making it sound grim.

this is pretty condemning information.

is there any strategy or hope for a long term disi mzr other than building?

Lets just say we live in fantasyland for a minute...

if somehow we were able to pick up a set of hitachi injectors that fit the stock fuel rail, but changed the angle at which the fuel sprayed into the combustion chamber, would that really alleviate the problem?

Sounds to me like the issue is the rings themselves. Maybe instead of spending a ton of money on new rods and pistons its possible to JUST replace the oil rings with a 3 piece design on the stock pistons?

just when i remembered why i bought my car you give me the reason why i wanted to sell it....

mazda engineers suck, not that we didn't already know that

Damn thats the first indepth theory that makes sense to me. I really wish I could get in contact with P3 and ask them what my motor looked like when they pulled it apart.

so where the piston seized, is where the injector is spraying fuel or is that the opposite of where the fuel is sprayed? that would be the "hotspot" cause by un even cooling from fuel spraying to only one side?

does that expain why lilguys piston crack like that? it was the opposite side of the fuel spraying

I ceep mine stock.. if it blows it does... (not that i think it will but..) the car is great! faster then most equal cars anyway...can use it on the track and daily driving, i put my money on suspension and rims etc...

If the mazda gods would allow me their fallen hero to have back only an intake and not blow that would please me.

If this was the case wouldn't we see CX7s blowing like crazy too? Most other DI cars are very similar in design (IS250s come to mind) wouldn't they be chucking rods too? Also if carbon build up is the issue, which I see everyday it is in DI cars, isn't that something that simpley running quality fuels and oils would fix? When I take apart any of our DI cars I can CLEARLY tell wether the owner has been using quality fluids or not.

ugh the problem lies with the EXPANSION of the piston from over heating. this in turn binds the rings against the walls and seizes the piston. if you were to ceramic coat the entire cylinder and piston id be willing to be we'd never seen another blown motor that wasent from sheer power.

There are many things working against this motor. However injector location is a big one. We (unlike diesels) are limited to that location because the spark plug is in the middle.

Original Mitsu DI engine designs did have the injector in the middle.

Yes, maintenance helps, keeping heat down helps, keeping boost down helps, but in the end the flaw in the design is blaring and it is bound to cause many more cars to fail on top of reducing overall engine life for everyone. The VW and N54 engines run a lot less boost.

Thats it!
Im gonna start throwing some 2 stroke oil in my gas. LOL

But seriously, what is the stuff gunking up the oil control. Carbon build up?
Maybe some serious leaning out would do the trick.
OT:
Travis @ Cobb indicated 12.7 AFR was ideal for our engine, I dont know if this came from testing they have done with their own car or what:
http://forums.cobbtuning.com/forums/...07&postcount=5

this car sucks but im still going to mod the shit out of it and get a new motor if it blows. haha

ill be looking to get rid of this shit in the next 2 years and get a Coyote Mustang

I want to see how many STOCK engines who has blown. Considering all of the engines here had has some kind of mod/tune.. perhaps that if it is many stock engines who has blown they maybe arent telling that here.. but if there were as many stock blow up´s as Tuned/modded blow up, mazda shurely would investigate in that. Dont think they will have a rep. of building bad cars!

Just below the red circle that shows the scrapes, you can see a ring that looks like where the piston had seized. Or is that likely just the impression made from when the rod was chucked?

http://www.mazdaspeedforums.org/foru...yl1exhaust.jpg
I also love how the angle just shows how the rod went right through everything

The lower line is likely where it had already broken.

Also, I would certainly use the highest quality synthetic oil in this car and change is often.

The VW FSI 2.0T motors also deal with oil burning issues. Do a little bit of searching.

this is great info, but like others have said how can you explain cx-7's hitting 100k + miles already and not having the issues that we have...

CX-7's? have u ever seen a modded cx-7 jay? lol i diddent think so. im not saying the problem doesent happen stock but as soon as u start modding it just gets worse.

is this making anyone else sick to their stomach? this is literally the most disheartening news i have heard in a while. that vulture thread was easier on me then this lol

They are not driven as hard, don't see as much boost, don't see as much heat, don't see as much load etc.

Lex....I'm going to sound like one of those guys but I've be with you since day one. You put in words well thought explanations. However, I understand this is still a "work in progress" discovery. I don't pretend to understand completely so here are some questions:

1. It was hinted at before but will a thicker oil band-aid this at least a bit? Higher octane as well?

2. The PTP burning oil fix also helps by minimizing the amount of oil ingested? OCC helps too?

3. What would we have to replace to avoid this or is going forged the only solution?

Keep it up man!

:biglaugh:

You must not have watched the video attached....

If this was an engineering flaw, as is what I understand Lex is trying to say, it wouldn't matter if it was stock or modded or whatever. The reason I don't quite buy this theory is because if there was some sort of design flaw it would have most likely been addresed after the first couple dozen cx7s tossed rods. In my experiance engineering flaws will generally happen frequently and predictably, this motor popping issue is neither. I appreciate the work anyway Lex.

yes I feel like i just got kicked in the nuts and gut checked at the same time....

Lex, what about seafoam in the oil 100 miles before oil changes to help clean deposits?

The flaw is a characteristic of DI and people like Lenny have already stated companies work in percents and even though our 180 deep blown motor list seems like tons to them all the blown motors probably don't equal 3% between the ms3', cx7, and Ms6.

Just making sure, this is what Im talking about.

http://www.mazdaspeedforums.org/foru...1&d=1253814697

Is this just previous damage, damage from removal, or possibly from the piston seizing up?

Oh I know and I agree 100%. It's the fact that we are under that magic number for Mazda to get involved that keeps me from believing this motor blowing issue is some sort of epidemic. For example, Lexus heard of maybe a dozen 06-08 ISs and GSs with corrodid fuel pipes and recalled all 300,000 cars from each year.

I believe that is the mark made after the piston got smacked cock eyed in the bore by the flailing rod.

damn!!!!!

Does anybody know how many ms3, ms6 has been built around the world?:06:

Yea, I was kind of wondering about that, if thats the case then wouldnt the wear marks be further along the wall? Down closer to where the piston seized up near the bottom of the cylinder?

I have a feeling the price of PI heads are going to go up!!! LOL!!

Someone call DCR and tell them to just drop the DI gig altogether and make us a PI/BT package good for 500+hp without worrying about any of these issues again!!!

it was something like 9k ms3 in 07 and 10 in 08 I have no idea about 09

Lets assume there was 10k made for each car each year that would be

40k ms3's
30k ms6's
30kcx7's?

100k of our motors in America alone

1% would be a thousand cars needed to blow. No company is going to look into 1k cars blowing their motors specially when they void half of them for the slightest thing out of stock spec and once your voided they don't apply you to their blown motor statistics your like a ghost to them. God only knows how many they have sold world wide all combined for eash car. Basically what I'm saying is we are screwed. When you saw the Subaru motors getting recalled trust me it musta been like a 10% or higher fail rate world wide that got them to move their asses.

Should be possible to find out how many are made exactly, but good guessing i think. Its the same engine in these cars but i dont think we can compare them with each other that much, i mean they must have different settings like in the ECU/ gear ratio/turbo boost or what not.
Specially the Cx7.. does it really have the same internals in the engine and so as the speed3,6?

When motors blow i dont think they wait until like 10% blows, it should be a huge problem if motors blow up stock! its not like it is some minor problem like windshield squeking or so.

But if they wait till 10% stock motors blow, well they do.. warranty or not, they shouldnt charge people to fix it if thats happenes. just speculations......:sasmokin:

What I said is real general but if what Lex pointed out is true its a DI characteristic and not just a ms3/ms6 thing. All the motors would show signs of it. If some one could get P# to answer how mine looked that would tell you. I had 38k HARD fucking miles on that thing.

Yeah second that. I'm willing to do a lot of little band aids if I can make my motor last longer. I'd really like to do an intake on my car because the power drop off at 6 anoy's me. But I don't want to hasten the damage to my rings. What are some idea's on it. Lets not get 30 posts of 'dude your screwed like the rest of us" Lets put some heads together and see what little tricks can be done to help out.

Maybe true.. but have we seen sign of it in the "other" engines? If that was the case, all these cars will blow up eventually u mean? Stock or not? Was the picture shown in this thread from a stock or tuned/modded car? (the first pictures in this thread)

It was modded but IMO I always felt that all the motors had a flaw that made its a candidate to blow.

Anyone know what the piston rings are made of?

thank you.

thank you

__________________________________________________ __________________________________________________ ____________


I find all this searching for answers very commendable. Keep digging and maybe soon we can build a bulletproof engine here with this ms3.

that aside, make no mistake.....for manufacturers such as Mazda or any other car manufacturer it's simple math. We tend to forget that we are a community of modded ms3's , and in the manufacturers eyes NOT ONE SINGLE blow up of a mildly - fully bolted ms3/ms6 even counts , simply because you MODIFIED IT. but pretending for a moment that they did feel the need to include all these blow ups it would still be a negligible %age of the whole production line for this engine.

you guys are comparing a 4k member forum vs the # of people that have blown up....the ratios are obviously much different.

I guess now the fail boat has completely sunk...

so even though Blackstone's UOA said I could go to 8,000mi on my next oil change with PP 5w-40 (the sample I sent them had about 5k on it), I probably shouldn't do that?

Its more like slowly tipping, just pray your car isnt on the side going in the water.

Im still wondering what where mods and info of the car from which the pictures have been gathered. What kind of mileage, mods, typical driving patterns, etc.

Not trying too be a dick or anything.. but putting on a lot of bolt ons and not tune or tune with a bad tune is a fail on these cars.. saying this because i havent seen any complete stock cars blown.

Not until some tuning company comes up with a tune and cracks the ECU on how its working on these cars, then whe can start modding etc...:thinking:

Wow, Lex definitely seems to be on to something here.

I know this has been asked a few times, but I'm going to reiterate it till there is an answer.

What can we do to help prevent against this, for aided reliability?

1. Thicker high grade oil, like 10w-30, or 10w-40?
2. Oil additives, "Engine Restorer" comes to mind, to help reduce cylinder wall scoring.
3. OCCs or VTA valve cover breather, to prevent oil burning?
4. EGR delete or restriction?
5. Make the car run leaner, SRI for un-tuned folks, or tune the AFI to be leaner?
6. Cryo-treated engine components, to reduce expansion from constant temp changes?
7. Seafoaming often, to reduce carbon build up?
8. Leave in the BS assenbly, to reduce motor vibrations?
9. This would take some machining, but what if we swapped the location of the plugs and the injectors?


I don't know about you guys, but I plan on taking this motor past 150k.

well thats great that you plan on it.... however i don't think the Mr.Disi himself plans too... :P

seafoaming won't help build-up in the rings

you need to run RICHER. rich=cool. thats why people with BT's and people who beat on their cars last. if you taking a long cruise make sure u dont just to 3k rpms the whole way there. get into boost every so often and vary the RPM's.

I drive my bitch like I stole it.

The ring issue is REALLY scary though, especially since I don't know the history of oil changes with my car. :gulp:

Call me a pic whore, but I want to see more pics of the carnage and findings.

this guy in sweden blew his speed in 6th gear. on secondmotor

http://www.mazdas247.com/forum/showt...hp?t=123754538

imo not really worried on why these motors blow. if i was i'd go forged. plus don't go by what one pic shows. if everyone that has blown posted a similar pic i'd believe him then.

but for now i'm more concerned on why i can't make more POWER.... figure that out first.

lol is anyone even viewing any other threads right now? haha

:headbang:

I have read about some people with JUST an SRI intake thats getting CEL codes: P0300 and P0303, thats random missfires and missfire in cylinder #3. Isnt that cylinder wich oftens blows?

should i buy stock in the largest manufacturer of these?
http://cnreviews.com/wp-content/uplo..._sale_sign.jpg

in a way this gives hope..

Lots of questions here and I certainly don't have all the answers. This is the motor the piston and rod are from: http://www.mazdaspeedforums.org/foru...-no-56k-19727/

Apparently low miles. Probably dyno oil used like Mazda suggests

No we can't change the location of the injector with the spark plug, the flame front will go towards the cylinder wall.

Not sure if seafoaming will do anything to the oil passages on the rings - best bet in my opinion would be changing oil often (I change it at 3k miles) with a full synthetic.

Also we know that knock is induced if the car is heatsoaked/prolonged driving and prone to knock if we get on it. Try and lean into it a little slower before going full race mode.

Cooling it off with some meth is not a bad idea.

However, and unfortunately the uneven heating/cooling of pistons and poor oil control along with cylinder wall washoff will still exist. It's as Darksun has pointed out part of the particular DI design in our car.

It should if you put it in the oil. At least thats what Seafoam themself advertises:
Motor Treatment - Sea Foam

"Safely frees sticky lifters and piston rings, removes carbon
build-up and oil residue"

I'd love to see more teardown pics of these motors that have blown and get more parts

you just made me want to sell my car:blackeye:

Couple common sense questions:
What makes you think the piston siezes prior to the rod breaking? How bout the rod breaking causing the piston to sieze?
What makes you think thinkt he piston always siezes under part throttle at low rpm?
If this was really the case here, they would be popping at higher rpm, more friction, more heat, more rpm obviously.
Sounds like more people reaching deep into lalaland to find answers.

here another good one, why are the rings rubbing in the 2x2 section of the wall and not anywhere else? Sounds like a bent rod prior to boomage.....this theory is fail

all I know is the only times I've ever had audible knock were both going WOT after driving for 3 hours in 90-110 degree weather. The motor being heatsoaked driving at 3300 for that long = knock

I think I might be hitting up the mitsu/subie dealership soon.

all this extended cruise bullshit, you guys realize that what you are describing applies to most cars right? not just this one.

I think Laloosh that all you can possibly say is fail.

The reason the scuffing happens midway is due to the lateral forces on the piston being largest during combustion at that point in its motion mr engineer.

Until you can prove anything further I won't waste my time.

actually the greatest forces happen at the top and bottom of each stroke genius. Not in the middle
care to answer any of my above questions? CAsue to me you still sound like some1 who googled how engines work

and here... we ...go!!!

Clearly you don't understand physics and where a piston is located with respect to the rod throughout the stroke and the lateral forces involved.

id ont understand physics.....lol.
Car to explain to me how the piston speed/force is greater in the middle then the top or bottom of each stroke? AFter all at the top or bottom the piston has to do a complete 180 in momentum.....right? humor me

He said lateral forces.

http://dictionary.reference.com/browse/lateral

ok i missed the lateral part, true, however they still should not be contacting the cylinder walls if the everything is according to spec. That motor either had bearing issues or a bent rod prior to destruction. Care to post a picture of where those marks are from a higher angle, this way we can see if those marks even line up with these lateral forces.

key word is lateral.

Peak cylinder pressure is after TDC

http://www.tvu.com/PSCylTEngwebFig6.jpg

Take a look at the thread for yourself. There are lots of detailed pics in pages 5 and 6

http://www.mazdaspeedforums.org/foru...84/index4.html

Gah, don't sell your car.

My analysis and digging are not to turn people away or scare you. I wanted to get to the bottom of what is failing in these motors in these odd odd conditions.

there no picture that shows if that even lines up with where the greatest lateral forces should be.

Notice how they have learned. In the EcoBoost the fuel spray is guided by the piston crown design up and away from the opposing cylinder wall.

http://z.about.com/d/mustangs/1/0/w/...coboost_05.jpg

http://z.about.com/d/mustangs/1/0/v/...coboost_04.jpg

now THAT is the kind of piston correction we need lol

like i said previously if your really an engineer tell me WHY we are not making power, what's wrong with the motor? not saying i agree with laloosh about the rods but i have grown to believe over the last year that haltech is right FUEL is our problem end of story.

i honestly at this point could care less about the engine blowing as many car manufactures have this problem(modified or stock). it doesn't matter, motors blow because of defect or who's behind the wheel.

stop posting your information(which i agree with laloosh) about nonsense that you don't have facts to back up. bringing this information up just makes people think differently about their car. your facts make up for a very small percentage of cars having this problem because it's not even in the same cylinder. yes it looks like 50% have been cyl 3(which supposedly were from the bsd which is now a myth) the others have been just random.

until your engine blows and YOU diagnose what made it blow, stop making these threads.

They are likely also running stratified fuel strategy for some of the time which we are not.


They call it university where I went to ... but here you go

http://www.mazdaspeedforums.org/foru...tml#post315755

Thanks Lex for your time on this issue. Maybe one day well have a MZR Motor fix thread where we can actually say we know what to do to ensure a safe motor build. Eh until then I'll enjoy my youth.