Interesting article: How AMG's Engine Factory Makes No Mistakes, But All the Horsepower (roadandtrack.com)

No - Nothing was loose inside the engine apart from the extra bolt found, when I take things apart each bolt/fastener gets placed in a zip lock bag and with a permanent marker described where it came from.

The area around the oil pipe running from the engine to the oil reservoir showed evidence of a being being hit by a road hazard object. I believe the PO had the damaged pipe replaced and tried to run the engine again instead of taking things apart the first time around.

It's like what "Stenzel" said it appears they did run the engine way longer than they should have.

Pending the completion of more work on other inhouse subjects I'll report the results of further inspection results here when available.

Thank all of you for your participation and feed back and hopefully this will help all of you (practicing preventive maintenance) to take car of these interesting machines.

Today I'm off enjoying the GTS in a quick 2 day roundtrip to Houston (400 miles) to show a Motor yacht. Would you buy a motor yacht from a guy that drives an AMG GTS?

I have absolutely no idea.

Well, unless there is a good "chain of custody" for this engine, we could not even say for sure that the engine had not been worked on post-delivery and the bolt dropped in at that time. I realize that's unlikely, but can we really say it was the original builder for sure?

I am in the "best not to say unless we are certain" camp.

I believe the head gasket would have had to have been removed and you can determine if it has been when you take apart the engine. If so, it's not too difficult to trace the "extra bolt" back to the builder.

Scott:

It seems logical to me that the “one man one engine” person would know almost immediately that they dropped and couldn’t account for a bolt in a open engine during assembly?

If the bolt couldn’t be accounted for on the floor or around the work bench then logic says they or another team member would have to dismantle the build until the bolt was located.

To hide the fact that the bolt was MIA would, in my assessment, be grounds for dismissal.

Jerry

And that's why Hendrik should NOT disclose who the engine builder was.. You guys have way too much time on your hands and are making a mountain out of a mole-hill..

I think as a precaution you should disassemble your engine to look for stray parts.

Hendrik, Thank you for taking the time to photograph and annotate the photos. The damage done is so extensive. Have you found any punctures in the oil pans that led to the engine running for a prolonged period without oil?

I hope you are well and have a great Thanksgiving.

Dave

Hmm, I wouldn't call an extra screw in a hand-build engine a mole-hill. What if it wasn't a punctured hose, etc., the engine goes and the car is out of warranty?

The sky is falling,!The sky is falling! IF ifs and buts were beer and nuts oh what a party we'd have.......

FYI;

For those that want to play along and are watching at home hereby my findings and some pictures to see for yourself.

The work so far: at this time the engine is completely apart and from what I have seen I now draw the following conclusion.

1. The PO driver did hit a road hazard that damaged the oil feed line running from the engine to the oil reservoir, lost some oil and perhaps stopped in time to avoid further damage.

2. Seeing the visual damage to the belly pan, damaged oil feed line and loss of the amount of oil they decided to pull the engine carrying subframe, crank case pan and oil feed lines from under need while the engine remained in the car, perhaps the rod cap on #3 piston rode was pulled to see the condition of the bearing, when all looked good and the engine still could still be turned over by hand they put things back together but never got the rod cap bolt for # 3 torqued correctly.

3. After things were put back together and now driving the car again the # 3 piston rod worked itself loose, the cap bolt came out and all the related damage happened in seconds.

4. The (2) broken bolt holes in the rear main cover plate demonstrates that the crank case pan was removed as without braking these (2) holes open the pan can not be removed from the engine block without first removing the flywheel (which can only be done with the engine out of the car).

5. After the second incident the engine seized and would not turn over in either direction and the PO decided to sell the car.

Best H

Thank you for sharing your findings. Would it be fair to conclude then that the bolt found in the passage was an unlikely contributor to the failure?

No I don't think so the bolt in the passage (located just below the R intake cam shaft ) was just stuck there, the bolts head was bigger than the opening in the passage.

Based on my findings, it all started due to a road hazard damaging the oil feed pipe to the oil reservoir and the loss of oil, which made the PO pull the crank case pan (instead of taking the motor out and do a proper costly/exam at that time) to inspect/look for any internal damage.

It is quite obvious to me that at that time they must have turned the motor over by hand and perhaps pulled to the # 3 rod bearing to check on it's condition before closing things back up.

I'm sure that if the motor couldn't be rotated by hand at that time they would not have closed it back up and tried to run it again. After starting/running it again the damage started when the # 3 rod bearing cap broke loose and the rotating crank shaft broke the # 3 piston rod, at the same time there was an immediate oil pressure loss (causing damage to all the bearings) and the motor seized within seconds after this. All the other rods where still connected to the crank shaft.

I'm sure that after this experience the PO decided to sell the car.

It's all good now, the car is doing fine and it's happy with it's new motor and perhaps with it's new owner, I wasn't looking for one but it found me!

Enjoy your cars

Hendrik, if we ever needed a reminder that when oil pressure drops to zero, we should stop the engine immediately, this is it! Thank you for the additional photos and explanation.

Dave

The two holes on the cover plate, since it can’t be removed without further dismantling things, I wonder if someone just cut the top halves of those holes to loosen the bolts with a flat wrench and slide the cover on off? Looks like a “Bubbas Kar Shop” move “hey, I could might fix that for ya!”

Hi,

Anyone who cares a little about mechanics should do that.

Unfortunately, you don't notice it. You only have an oil level warning.
No oil pressure monitoring. Not even on the Can bus.
It just doesn't exist. Not even a pilot light.


Who wants to prevent here:

A simple oil pressure switch (recommendation: NC / open @ 0.8 bar / 12 psi) in combination with a buzzer and / or indicator light, can save lives. :-)

The thread of the stock test connection point (measuring is between oil pump and oil gallery)
M12 x 1.5
Longer connection/adapter is an advantage. The best way to access it is from below. (attach pics.)

Oil pressure switch (One wire, grounded switched) ----> control device minus / control device plus ----> terminal 15 (ignition) or better with buzzer, terminal 87 (engine running)

Info:
The oil pump is regulated in 3 stages.
1 bar / 14.5 psi (idle)
2 bar / 29 psi
4 bar / 58 psi

If you don't want to pull cables into the interior. Or be in hurry ... Quick and dirty ;-)

Mount a ground switched, (one wire) Oil Presure Switch. Connect the oilswitch wire, parallel to the level indicator of brake fluid reservoir.(= Brown/white wire).
If there is no oil pressure (engine off), one red brake warning lamp, lights up. If there is oil pressure, it is off and brake fluid level continues to be monitored.

Just to make it complete: If you have alert, check both, brakefluid and oil Level.

Note:
Made this quite often at other MB, but not yet tested on GT. (I retrofitted an oil pressure gauge, with an alarm).
I looked at the circuit diagrams, it should work.

May also be that a resistor is still needed.However, it maybe that you get an error message (brake fluid level) after starting and with "o.k". you must reset.
But it would be simulated quickly.Just bridge over the connector of the brake fluid level sensor. Remove the connection after the engine has started.


Kind Regards

Stenzel

Oil pressure test point, with retrofitted oil pressure sensor.


Prüfanschluß mit Öldruckgeber. 1

Prüfanschluß mit Öldruckgeber. 2

Hendrick & Stenzel