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p.s. Confirmed bent rod on cylinder #10 as well. I did not ask for that to be performed, my mechanic did it on his own. I am going to go over today to talk in person as I am getting some conflicting information. Now, he doesn't think the valves are bent anymore and the scoring is only at the top but he thinks that's from him trying to find TDC. That leaves so many questions open, like how did fuel and oil mix? Why was there tons of blue smoke coming out of the exhaust? Why was there a loud clank when the car seized? What clanked?
This is all speculation and theory since none of us are looking at the actual engine.
Well I’m still going on the assumption you had hydro lock and that was due to at least 2 injectors filling up their cylinders. probably #10 failed also and dumped its fuel load out the exhaust. Blue smoke would be oil and these engines do drink oil. I’ve never been behind a car on the hwy when it sh*t the bed. Could have been a lot of gas and oil. Only you saw the puff.

Engines are designed to compress air. Something has to give. It’s generally the con rod, otherwise it’s the block, especially in these unsleeved designs. I’m assuming that the valves were retracting as they should have been and the piston was where it should have been in its stroke. You may also have a cracked crank. That will certainly help account for the difficulty in rotating it by hand.

we don’t know what your scoring looks like, but there’s a big difference between scoring from rings and scoring from the piston. P-Chi’s pictures pretty clearly show that.

how did he know the rod is bent? We’ll assume he’s making the same assumptions we/I am. Bore scoring as well as measured depth comparison from TDC/BDC across cylinders. Maybe the sh*t is sideways like the other guy had. Unless he’s dropped the pan and removed the head and pulled the cylinder, that’s the only way to have visual confirmation, if we don’t go by deduction.

Maybe he didn’t do the compression test correctly and that’s why there was the huge pressure loss. You asking your mechanic about air noise from the intake/exhaust/coolant tank or oil neck definitely tells him you know what’s up. People that know that generally are not asking mechanics to do compression tests in the first place since it’s not too hard to do it yourself. For the cost of the mechanic to do it you can buy the tool and a few 6 packs. Just need an air compressor too.
 

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p.s. Confirmed bent rod on cylinder #10 as well. I did not ask for that to be performed, my mechanic did it on his own. I am going to go over today to talk in person as I am getting some conflicting information. Now, he doesn't think the valves are bent anymore and the scoring is only at the top but he thinks that's from him trying to find TDC. That leaves so many questions open, like how did fuel and oil mix? Why was there tons of blue smoke coming out of the exhaust? Why was there a loud clank when the car seized? What clanked?
if your mechanic did not get an ok from you first, then he is doing it on his own time.

Why would anyone do that?

Is he concerned his previous work had something to do with it?
 

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Discussion Starter #147
This is all speculation and theory since none of us are looking at the actual engine.
Well I’m still going on the assumption you had hydro lock and that was due to at least 2 injectors filling up their cylinders. probably #10 failed also and dumped its fuel load out the exhaust. Blue smoke would be oil and these engines do drink oil. I’ve never been behind a car on the hwy when it sh*t the bed. Could have been a lot of gas and oil. Only you saw the puff.

Engines are designed to compress air. Something has to give. It’s generally the con rod, otherwise it’s the block, especially in these unsleeved designs. I’m assuming that the valves were retracting as they should have been and the piston was where it should have been in its stroke. You may also have a cracked crank. That will certainly help account for the difficulty in rotating it by hand.

we don’t know what your scoring looks like, but there’s a big difference between scoring from rings and scoring from the piston. P-Chi’s pictures pretty clearly show that.

how did he know the rod is bent? We’ll assume he’s making the same assumptions we/I am. Bore scoring as well as measured depth comparison from TDC/BDC across cylinders. Maybe the sh*t is sideways like the other guy had. Unless he’s dropped the pan and removed the head and pulled the cylinder, that’s the only way to have visual confirmation, if we don’t go by deduction.

Maybe he didn’t do the compression test correctly and that’s why there was the huge pressure loss. You asking your mechanic about air noise from the intake/exhaust/coolant tank or oil neck definitely tells him you know what’s up. People that know that generally are not asking mechanics to do compression tests in the first place since it’s not too hard to do it yourself. For the cost of the mechanic to do it you can buy the tool and a few 6 packs. Just need an air compressor too.
I got an air compressor :) I am quite handy. I don't think he is trying anything nefarious. BTW, the puff of blue smoke was gigantic like 20 feet in diameter
 

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Discussion Starter #148
if your mechanic did not get an ok from you first, then he is doing it on his own time.

Why would anyone do that?

Is he concerned his previous work had something to do with it?
No, he is doing it as we are somewhat related and he is taking care of me.

p.s. I think he did not realize the problem was as serious initially, he thought changing injectors may do it. Then the cylinders failed compression and he realized something worse happened and started digging deeper I guess.
 

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Discussion Starter #149
Here's what the cylinder #10 wall looks like.
Also, I got details on the injector leak. Only #10 seems to be defective and leaking. It does NOT leak with ignition on so there goes that theory. It leaks after attempting to crank the car only then it starts leaking and it keeps on leaking. Mechanic had no answer as to why #8 and #9 had wet spark plugs as the injectors on those 2 cylinders are not leaking. Weirdly enough, the spark plug for cylinder #10 was dry.
 

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Good update. That’s a bent rod and partially locked open injector. Very disturbing since your filter was not in service for too long. Looks like what P-Chi has. So only 1 bad injector then?? I thought you said there was a bunch of fuel in 8&9. Max pressure is 6 bar so sounds like it leaks when there is pressure above a certain threshold.
 

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Discussion Starter #151
Good update. That’s a bent rod and partially locked open injector. Very disturbing since your filter was not in service for too long. Looks like what P-Chi has. So only 1 bad injector then?? I thought you said there was a bunch of fuel in 8&9. Max pressure is 6 bar so sounds like it leaks when there is pressure above a certain threshold.
We do not have an explanation as to why 8 & 9 had wet plugs. Those 2 injectors are not leaking now. They may have leaked at some point maybe? #10 plugs were dry even though that cylinder obviously hydrolocked and the injector is still leaking.
 

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On my Land Rover if battery is low and thus starter runs below a set speed ecu will not fire plugs in order to protect against backward engine rotation .
Perhaps in your case plugs did not fire on attempted restart due the high resistance of rotation due to engine damage resulted in the starter rpm’s below set point shutting down ignition.
 

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This post makes a case to never open up an s85 unless an actual failure

http://instagr.am/p/B5ZIlL0pUe9/
Hello ticat928,

Ignoring the issues we are finding, does not mean that they will not happen again. Some engines will go 200k, some will fail at 50k.

I believe in my work and will rebuild TWO s85 to my satisfaction and standards. I am not on a clock, so I can expend as much time as needed to make SURE they will be perfect. Dealers and shops are dangerous because of the "job rate" policy. Cutting corners makes more money for shop and mechanic.

Great local shops should be praised and I hope some are discovered and shared on the forum.

Mr. P
 

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It's all a numbers game. BMW probably did build a few golden engine). But the reality is that many engines do fail. And let's be real, on any other platform, those 215k bearings would be still considered to have worn terribly.

Just like there are some people who smoke for 80 years and never develop any health issues and people who do everything right who get massive MIs at 40 - the outliers aren't what you should base decisions on.
 

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The outliers are Original owners that are car enthusiasts that say hell no I am not going to wait 13,000 miles for a free oil change.

As fiftytwoeighty says most are “Renters” with the implication being they do not intend long term ownership, keeping perfect mechanical condition for second owner is not a priority
 

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The outliers are Original owners that are car enthusiasts that say hell no I am not going to wait 13,000 miles for a free oil change.

As fiftytwoeighty says most are “Renters” with the implication being they do not intend long term ownership, keeping perfect mechanical condition for second owner is not a priority
So you think there's not a single original owner who did oil changes more frequently that still ended up with a failure? You'd rather believe a proven conman who's in the business of selling engines that the engines are durable?
 

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I do not believe anyone unless data is irrefutable or I can verify by repeating results.
I have been buying new cars since 1986 and keeping them for over 10 years, none burned oil none had a spec of varnish in motor, yes I am OCD when it comes to maintenance

So you think there's not a single original owner who did oil changes more frequently that still ended up with a failure? You'd rather believe a proven conman who's in the business of selling engines that the engines are durable?
 

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I may complain about bmw quality of design, but there is no way that the tight tolerances and quality controls systems they employ would allow a golden engine.

I know that theory gets floated many times to rationalize observations that seem unexplainable.

It is simple the first 700 miles on new car are most consequential followed by the next 3000 miles.

That is what determines if you have a golden engine.

BMW does not care what you do , the s85 was designed to statistically just meet warranty requirements even if owner does not care to properly maintain any type of mechanical equipment (like my past neighbor who never changes his oil on his lawn mower, just buys a new one every 3 years, while my $60 B&G lasted over 20 years)


It's all a numbers game. BMW probably did build a few golden engine). But the reality is that many engines do fail. And let's be real, on any other platform, those 215k bearings would be still considered to have worn terribly.

Just like there are some people who smoke for 80 years and never develop any health issues and people who do everything right who get massive MIs at 40 - the outliers aren't what you should base decisions on.
 

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I may complain about bmw quality of design, but there is no way that the tight tolerances and quality controls systems they employ would allow a golden engine.

I know that theory gets floated many times to rationalize observations that seem unexplainable.

It is simple the first 700 miles on new car are most consequential followed by the next 3000 miles.

That is what determines if you have a golden engine.

BMW does not care what you do , the s85 was designed to statistically just meet warranty requirements even if owner does not care to properly maintain any type of mechanical equipment (like my past neighbor who never changes his oil on his lawn mower, just buys a new one every 3 years, while my $60 B&G lasted over 20 years)
I don't buy it. If that were the case, all of their engines would show similar failure rates. Unless you think only M5 and M3 owners get a little lazy on oil changes.

They just didn't adequately test the product. If those first 700 miles were going to set something up for failure, it'd manifest very quickly. Not at 50k miles.
 
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