benz_addict

Hey all. Update on the 55. After my rebuild back in 2011 I have put approx 60,000KMS on it since then. Smoke started coming out the exhaust after start-up, heavy smoke under acceleration and power loss were the symptoms. Did leak down test and cyl 8 failed so bad, and 40PSI under compression. Time to pull the heads and found this:



The gashes in the cyl 8 wall are so bad and deep that there is no way I can get away with a simple rebuild this time. This engine has to go. It close to 300,000KMS of hard throttle light to light bashing, circuit track, drag strip miles on it so it gave me what it's worth.

Anyway time for a swap! No biggie, still got my tuned V12TT I can beat around town.




New engine that is going to go in:




stay tuned

RAWE55

I actually have nightmares about this stuff. So sorry to hear that it happened to you a second time. Bright side is that you have a fresher engine. You could even bore out the old one and throw some darton sleeves in. (Just speculating)

OZZYAMG

Hi

The nightmares about this type of thing must be common for us Melbourne E55 owners. I also think about this and what I would do if it happened to me.

I hope all goes well and the car is on the road sooner rather than later.

Regards,

OZZYAMG

StarvingArtist

Sorry to hear it man. Why is it always #8? Lean injector, or is there another factor?

Yacht Master

Its the end of the line, last injector on a fuel system that dose not have a return/recirculate line.

kompressede

Do you have a looped fuel rail, and its hard to tell from the picture but is it just #8 that suffered the damage?

Hulk

Sorry to hear bro, what were your mods?

GregMB

Low fuel volume can come from many places..... I'd be curious about the last service interval of the in-tank fuel filter and replacement of the factory fuel pumps as well.

We've seen plenty of examples where guys skip that maintenance (at the 60,000 mile mark) to save a few bucks, but end up with a melted fuel pump wiring harnesses (due to excessive resistance of the clogged filter).... and restricted fuel flow.

The looped rail can add some "margin" to the factory design, but ultimately if there isn't enough fuel volume arriving from the pumps it doesn't matter what "shape" your fuel rail is...... straight, round, trapezoid, sinusoidal, etc.


-G

HeissRod

I thought people were debunking the looped rail around here a few months ago?

kompressede

Agreed - Fuel filter is very important.
A looped fuel rail typically (I thought) distributes the fuel more evenly to all the cylinders? Therefore, shouldn't all the cylinders suffer if the volume isn't there?
That's why I was wondering if in fact the car had a looped rail??
This is just speculation - Waiting for an update from the OP?

Toadster

dang that sucks....

would be interesting to see if someone could design a dual-add-on pump design where you have secondary pumps feeding - one pump per bank

jcjmw

Not the rail itself but the vendor who was selling it, TTM. The looped rail did result in increased pressure (?). I am trying to remember who actually did a test on it but it does work. Not like an immense amount but I remember there was tangible tested result of improvements or fuel benefits due to the looped rail.

HeissRod

Gotcha

Hulk

SLR uses a looped rail

GregMB

REMEMBER:

Pressure does not equal FLOW.....

I can run a 1/8" fuel line to my engine at very high pressure, but I won't have enough FLOW (fluid volume) to feed the engine.

A clogged fuel filter will result in very high pressure (before the filter) but only as a result of the flow being restricted.... the fuel coming out the other end is slowed to a trickle and can't keep the engine from going lean.

When you run out of fuel from the pumps it doesn't matter what shape the fuel rails are.... just get out your checkbook and tissues.


-G

viren.89

Sal,

When did you get an E55 ? Did you sell your V12 ?

For the issue on hand- GL man

Need4Speed

A moment of silence for such a good motor..........

Oh well engine swap time !!!

OCKlasse

You're replacing all those ABC lines, right? Do it now!

trackjunky

iTrader: (1)

Just a n00b here trying to get educated. If one or more cylinder is running lean won't it throw codes first? Or can it be so severe that it can just blow up the engine instantly? This is assuming that it's a fuel delivery issue to one of the cylinders, right?

MindBend

Yes! I second this! Have replaced 3 in tank filters now on low miles cars and all were crapped up. DO IT!! When increasing performance, the factory-designed margin decreases.

On the latest change, I noted the fuel strainer on pumps had gunk all over them too. (Much coarser filtration, but flow interference, just the same).

Each side costs appx $500 for parts...nominal cost compared to new engine/rebuild.

Sir-Boost-a-Lot

iTrader: (1)

Cost and aggravation! I want to drive, not repair!

MindBend

Agreed. An ounce of prevention is worth a pound of cure.