Blown motor pictures, with details
 

http://www.mazdaspeedforums.org/foru...tml#post216612

Here you go guys, we have several ideas that we will be working on here in the next few weeks. If all goes well we will have the blown motor issue fixed as well as all your knock. Stay tuned.

so pretty much you stated that at "CRUISING" speeds the rods tend to bend due to excess oil? wtf

^^ That's all I can get out of it as well..

Not just cruising, but long, or extended drives which make the block heat up.

I think I remember Ken@PG say something about heating issues causing motors to pop as well, not sure exactly what his theory was though.

And Comsic3mps just blew while on a long trip...

Yes, but I feel that it has to be a consistant cruise with zero to no boost on the motor. I will have more details to post on here soon.

There is the heat issues, but that is something that we need to address at a later date. Our motor shows no signs of blowing up from heat, it hydrolocked plain and simple.

Yep, and if you look at a lot of the motors on the "blew my motor thread", you will see that a lot of those blew after a trip or driving for a while. There is only one thing that could lock a motor up to look like a hydrolock, and that would be oil. The DI cannot put enough fuel into the motor to cause this. Hence the only other fluid in the motor would be oil or antifreeze, our cooling system was full and there were no signs of antifreeze in the motor or intake... this only leaves oil for the motor to lock up on. Yea.

Subscribed and interested in the results

Thanks, we should have more details here very soon on the issues and the potential fix.

Looks like I wont bee going to EECMM....

Ill Sub to that...

*note to self*

Flog car on long drive

Looking forward to a fix to this problem...

I have seen many,many blown motors in my time but I have never seen any with 4 bent rods and still have all the rod bearing be in good condition. In fact I'm not even sure its possable? For there to be enough force to bend the rods there has to be enough force to squeeze the .002 oil clearence out of the bearing serface and make direct contact with the crank.

I don't think the engine would run if there was enough oil present in the combustion chamber to cause hydrolock and if it did it would be smoking like you wouldn't belive. What did the plugs look like?

Have you seen any blown DI engines? How many?
These damn motors are a mystery.

No blown DI motors. I mostly build high horsepower motorcycle motors. Too give an idea on how much power I get out of a motorcycle motor, the Speed 3 makes maybe 240 HP @ the wheels with a 2300c.c. turbo engine. My 1070c.c. N/A GSXR engine makes 190 HP @ the wheel and 230 HP at the wheel with a small shot of juice. My engine is not the most powerful engine I have built either. But none of them have ever bent all 4 rods at once. the bearings will fail before the rods will bend.

9 times out of 10 bent rods come from detonation. When the air fuel mixture is getting fired off before the piston reaches T.D.C. all the energy has to go some where and usually will hammer the bearing, burn the piston, or bend the rod.

Di engines mechanically are no different than PI engines. I don't understand why everyone thinks they are such a mystery.

I agree 100%. Other than the intake and injectors the internals of the engine are the same.

I have close to 60,000 miles on my speed6. And most of the miles are trips to Louisiana from Michigan close to 1,000 miles and avg 30miles. So no boost for me.

More info posted deep in that thread. Take a look if you get a chance, thanks.

I am in agreement with this, beat on car like some have with no problems and you will be good.

Working on it.

I agree 100%, problem being were were not under boost, we were not running hard. Thus the pistons just stopped in the motor as if we had been under WOT and full boost. Had more motors popped while under WOT and preignition was pressent then I would have to agree with you. Our motor made a bad noise, then lots of smoke then all was good till we started to hear the noise 10 seconds latter. I had beat the death out of the car before this and I have never taken it on a long trip with this MPH posted for so long (60 to 65 mph the whole trip). I have taken it on longer trips running at 70 + and never had this problem.

The crank bearings looked a tad squished but never checked them to verify and the lower end of our motors move around a good deal due to the lack of any real support for the crank.

Why does everyone think that they would smoke if there was oil inside the combustion chamber? This is a one time event, this is not an on going thing. There is a very good possibility that motor is collecting oil on the floor of the manifold and it sits there till you go WOT or change your driving patterns. I can garrentee that it was a hydrolock condition that locked these pistons up now. We have had to motor builders look at them and both stated that the rods bent with the rotation, indicating that it was something that stopped, and held the piston in place as the rod rotated around the crank. Any pre-ignition or ignition timing event would have shown signs in the piston head from broken ring lands to detonation specks in the top of the piston. None of this was pressent, but we did get a lot of oil out of the intake manifold and even more out of the exhaust side.

Sorry but the are very much different. Both Wiseco and JE have been working on designing pistons around the DI motors. They are very much as different in design as an apple is to an orange.

Jon - I have the perfect fix - its what I do on road trips!!!

You can sell it in your electronics section of your website and it will fix all problems.

It allows you to cruise at 3700 mph in 6th gear on the highway - its called the valentineONE :)

Allows me to do about 100mph on cruise control. Just got back from 965 miles of driving in 60 hours.

In all honesty though - your dedication is there as always. Keep on trucking. I know I will be investigating this myself and seeing what your solution is when I build to fix my piston ring wear.

So taking it easy on our car, say 6th at 65 over many hundred miles, caused engine failure. Damn it.....just damn it! I guess I won't feel bad downshifting into 4th and going WOT on the freeway any longer because this actually has saved my motor from popping....in theory.

didn't you swap out the stock pcv out completely? hows that working?

Same as a stock setup. All i did was drilled out the stock pcv cover - threaded the whole and screwed in a pcv valve from a parts store. My motor is spewing oil however because I have TERRIBLE compression. I am going to blue print and build in august or september. The only decision left is 10:1 or 10.5:1

All internal combustion piston engines have 3 lower end components in common. Pistons, connecting rods, and a crankshaft even though there are many style and shapes of those 3 components they are all basicly the same and do the same job. This is what I mean when I say there not any diffrent than any other engine. It's more like comparing diffrent types of apples, there both apples but diffrent. A Wankle and a piston engine would be apples and oranges.

The piston might be very diffrent from any other piston but it's still a piston and does what all the other pistons do

Is there anyway that the DI could cause the cylinders to not get enough lubrication and with the heat cause the pistons to semi-seize in the bores putting stress on the rods causing them to fail?

would the added pressure of the DI system cause fuel to blow by the rings hindering lubrication? I know there's allot of talk of fuel in the oil...

During high heat conditions oil would lose its viscosity and not cling to the cylinder walls as well....




I'm just grabbing at straws here though... I don't really know shit... LOL!

I would have to disassemble and inspect a blown motor to know for sure what happened to it. Just looking at pictures its impossable to tell.

Anything is possable, even the combustion chamber flooding with oil.

I have a lot of Km on my car 98k Km. I do a lot of constent speed driving and is usually around 3k RPM. As of late I have been feeling some different vibrations. If the motor idles it doesn't do it and if on the throttle slowly acelerating it doesn't happen.

I was thinking it was clutch/tranny. My suspension is going to be replaced (springs/sturts/front sway) this weekend and I suspect that could also add to the feelings I am getting. I have been getting P2188 CELs 2 or 3 times a week in the winter months and fewer now that it has warmed up. Car feels fine when on the power but I want to make sure that if my motor is going to go (knock on wood) it does it before 100k Km and end of warranty.

What signs are there in the motor that a rod(s) is/are bent?

If this occurred it would likely be a cascading condition, leading quickly to the engine seizing entirely.

Is it possible that excessive heat could cause the oil to lose it's lubricating properties and become a hazard of hydrolocking?

While your theory of fuel dilution in the oil sounds like the most logical , I can't help but try to think of any other possible causes. Perhaps a combination of several factors contributing to the failure. Example: Heat + poor oil control + fuel dilution + rapid oil breakdown = BOOM.

I don't know man. To be honest, I'm not qualified to make assesments on this complex of a problem. I'm pretty new to these high tech 4 bangers. I attended the school of hard knocks which means no formal training, but if your carburated V8 needs work then I'm your guy. lol

Whatever the problem is, I think I speak for all of us here when I say that the hard work and dedication of you and so many others to finding the cause and cure for this will be greatly appreciated for years to come by all current owners and new comers!

Thanks again and keep up the good work.:biggthumpup:

I drive my car an hour each way to work an back and have done so for over 2 years now. I do beat it on side roads and and sometime on the highway. For the most part i try to get good mpg on the highway though.
I wonder if the BSD mod can make this worse since it causes a slight increase in oil pressure.

Yes and no, its like compairing a 2 stroke to a 4 stroke, yea they use pistons and rods and a crank but... the heat and design parameters are different for those items. There is a ton of thermal switching in a DI motor. When the fuel hits the cyl temps drop 350 to 450 degrees, this is the cooling cycle that makes DI so great. But this also makes for a very bad situation for the piston (kind of like heating a part up till its glowing and then dumping it into a bucket of water). DI pistons are designed different then a conventional PI piston. Yes the same rules still apply to the rotating assembly but its the slight differences that we are looking at, not the big ones.

There is a very high dillution factor with our motors, no idea if the PCV system and EGR system are playing a part in this. We are going to correct the EGR issues and then address the PCV system. Should have pictures up here very soon with testing starting shortly after that.


I would have to say that would play a part with the turbo seal leaking more then additional oil making it to the PCV system. But then again, if more oil is getting to the top of the motor the could make the PCV system become overwhelmed. We will know soon enough, thanks.