Mercedes 190e 2.3-16V Turbo

[jeandersson]

Hi guys

Engine and transmission is coming apart for inspection shortly. Is there anything specific you would like pictures of?

[Nagilum]

Bearings/pistons cylinder walls? ;P

[Steffen102992]

Hi Jean, I wanna see, how you killed the 722.6xx....what was the weak point!

[jeandersson]

Hi Jean, I wanna see, how you killed the 722.6xx....what was the weak point!

Hi Steffen,
Believe that I overheated the transmission oil. So I would not really say that it was due to a weak point. Seems like you can kill any automatic transmission if the oil is passing a certain temperature. Have increase my cooling capacity now, but are still not fully satisfied. When pushing the car it's still possible to have the temperature in the transmission to raise slowly towards unacceptable levels. Below are some pictures of the two times when I damaged the transmission. In some cases the clutch packs got welded together. In other cases the small tooth got broken off (after the packs got welded I suppose). In one of the breakdowns the aluminum in the B1-clutch was melted, so I guess I didn't stop in when slip started to occur.

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[jeandersson]

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That all pictures from the transmission damages.

[Steffen102992]

Holy Moly!
Never seen that before, I repaired many of them in my career, but this is unbelievable! I thought if a 722.6xx could not resist a powerful engine, then no other tranny will do it.
I saw a 722.5 with similar damage, but this was driven without oil or less oil.
It was caused by one single run? (overheating)

[jeandersson]

Holy Moly!
Never seen that before, I repaired many of them in my career, but this is unbelievable! I thought if a 722.6xx could not resist a powerful engine, then no other tranny will do it.
I saw a 722.5 with similar damage, but this was driven without oil or less oil.
It was caused by one single run? (overheating)

Hi Steffen,

Thanks for the interest and comments. The overheating was caused by several runs with to short cool down in between. Maybe 3-5 runs on the 1/4mile. Once it started to slip the temperature raised incredibly fast. So I believe that the oil was destroyed gradually by the overheat and then all mechanical damage occurs more or less at once when oil lost the capacity to remain the oil-film. But as said before the root cause it that I continued to push it. New rule is to not pass 95 Celsius, not because I'm sure about that number. But rather just to have some number for myself to refer to. Once in a racing situation it's easy to think "just one more it will last"...

[jeandersson]

Hi again

So engine have came apart. And it seems that it was not about to fall apart this time. Only notice I have taken is that the cylinder walls seems to have some corrosion, maybe due to the long times between usage and the E85 fuel. Cylinder walls also has some wear in the area were pistons/rod is pushing the most. But nothing severe. So my plan is just to clean the cylinder walls a little with Scotch brite and reinstall it all. Didn't take any pictures of bearings but they are looking just fine. Shall see If I can remember to take a picture before assembly. Also noticed a crack in the exhaust manifold that has to be welded. It's a relief to see that the oil pump is still properly fixed, chain tension good etc. Pictures below.
Any questions, just let me know

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[Nagilum]

I wonder about the rings - where are they coming from? I doubt I've seen that before.


And there are 2 scratches one is straight, as you'd expect if they have contact (shouldn't be?) - but the other is slightly curved. You know what caused that?
Overall: I'd say the engine looks rather good for the power you squeeze out.

[jeandersson]

I wonder about the rings - where are they coming from? I doubt I've seen that before.

And there are 2 scratches one is straight, as you'd expect if they have contact (shouldn't be?) - but the other is slightly curved. You know what caused that?
Overall: I'd say the engine looks rather good for the power you squeeze out.

Hi Nagilum,

Piston rings are from Wiseco, came with the pistons. I believe that the scratches are from dirt or sharp edges during assembly. So basically my own fault.

Some speculation regarding the corrosion in the engine block is that it's due to the fact that I run alcohol fuel (E85). Some suggestion from drag-racing forum is that when running alcohol fuel you should not start the engine for short intervals. Like when I start the engine only for moving within the garage. If doing short starts, moisture is formed and due to the long intervals between running the engine cylinder walls starts to corrode. I believe this can be correct, I have noticed that during the first 5-10 minute of running the engine water/steam is coming from the exhaust system.

I also have relatively short connecting rods. This could be contributing to wear on cylinder wall.

It will be interesting to see how the engine looks after another one or two seasons of running at these power output.

[nightXmare]

typical e85 "rust" you got it ...e85 is the best and worst fuel in one

got that one some detonation? on the photo it looks like the upper leften side got some detonation area

[jeandersson]

typical e85 "rust" you got it ...e85 is the best and worst fuel in one

got that one some detonation? on the photo it looks like the upper leften side got some detonation area

Considering the amount of boost we can run without seeing detonation, it's still a fantastic fuel for me. No problem to replace the engine block every second year if needed.

I have not seen any sign of detonation when inspecting the pistons in "real life" maybe it's the camera/photo who tricks the eye.

Have been quiet here for some while. That's because I'm installing a roll cage like this one https://finess.se/wp-content/uploads/900.jpg
It's not a pretty sight when done by myself, especially at those spots were the car has corrosion since before nice welds have been really hard to achieve. I'm worried that some enthusiast in the forum might want to kill me if I show how the car is being even more destroyed (for someone who loves to keep these cars genuine).

[nightXmare]

naaah... the german mercedes scene might be a bit "old fashioned" if it comes to modifications, but we have some realy crazy guys too (but they are not showing all their cars and builds )

i like what your doing! my om605 build will get a safety cell just bacause it stiffs out the whole chassis

pls report on

[jeandersson]

Hi again,

Sorry for the long time without any update. Latest project have been installing N2O in order to get better starts. So I ended up destroying the converter and are right now waiting for it to come back from repair. As promised some pictures of the safety cage/roll bar. It's made to be fully detachable so that I can take passengers in the back when we are not on the drag racing track.

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