i think the m103/104 are basically same engines, quality. Over the years some minors changes were for sure implemented. But since Brabus probably modify the blocks to their own specs, they will treat any stock block as a core exchange.
But i have noticed over the years that the very first m104 3.0-24 (the one engine the usa didnt get)
Those engines are prone to burn lots of oil much sooner than the M103 3.0.
This is only an observation, no hard facts.

__________________
Jay,
-----------------
-1995 Blue W202 C36 AMG (M) SOLD ;(
-1995 Black W140 S500 (Lady)
-1992 Black W124 E300 (Dima) (Ex-Mosselman
Twin turbo Kit).
-1988 Black W124 300 E 4-Matic.(Nadeen)
-1983 Brown W126 500SEL.(Old Lady)(Sold)
-1981 Gold W123 280CE.(Dareen)(Sold)
http://www.youtube.com/user/jayrasheed

Ok så to day all the pistons were romoved from the engine.

And they all seems to have run a bit hot, but they are absolutly in very good condition all the way around.

BUT,,, all the lower compresions rings where broken into several pieces.
None of the other rings where damaged, the top compresion rings and the oil rings where all in one piece, but just very slappy/soft.

But then my big question is, why on earth is it only the lower compresion rings that is broken in several pieces on ALL 6 pistons

one of the piston rings where brokken in over 10 pieces for every ― cm. the piston ring where broke over an 5 cm. area.

The next huge problem is "where to get the rings???
BRABUS can sel me the pistons but they are not in stock but can be ordered and hold on now, the message was:
Piston incl. rings each 711 Euro net are they gold plated with a diamond inprinted

The pistons is Kolbensmith pistons and my guess is JR pistons must have a simular model to replace them.
I got a price to day at 210 Euro for those, but I dont now if they are quite the samt quality? but they should be forged to and BRABUS is likely to use JR pistons to day I was told.

The price at BRABUS is for sure there supplyers price times 2 or 3 because thats the way profit works so do anyone know (if the shop gives my pistons the dead kick) where I can buy kolbensmith pistons? I have searched all day without finding any thing on google?

In the Wis CD the engines should be the same, but you are right that the M104 is using a bit more oil, but htat has to do with the 24 valves and the higher revs at 7000.
If you use the power then it will use oil, other vice it will be the same as the M103 witch also uses a bit oil if runned at high revs.

A funny experience that I onced had where when these cars where faily new in the 1998 I went for a holiday and drove through Germany, and in every single gas station we made a stop for gasoline, a service gas station dude went over with a 1L. oil and asked if he should check the oil level.
And I meen who needs that in every stop so we asked why he dident offer this for some of the other customers, his answer was that is was well known that a mercedes is and should consume some oil drivin fast on the autobahn. many of there pendlers travels more than 500 Km each day to get to work and they tend to use up to 1L. for each 1000 Km. if you drive them above 160 Km/h raving down the auto bahn, they are simply design this way, and therefore they found it very usefull to offer the oil check because most mercedes would want this check anyway the way they use them there.
Just a funny story and I dont know the truth about it, but I do know I have driven a lot mercedes and they all tend to use a bit oil when pushing them down the autobahn and the M104 were a bit more but not much more oil hungry.
The main reason should be the head with the 24 valves my shop said he have repaired a lot of these heads and itīs always the steam seals valve seals that are the problems and very rare the valve guides. the M103 does have a bit problems with the valve guides and the cam that wear out rather quickly on the 260E and the 300E 150.000 Km. is not rare to see when the cam needs to be changed. again this problem is completely gone with the M104 3.0-24 so general the M104 is the engine to go for if you should point them out he said.
Well that was a bit of topic I went here, but still nice info.

You are right on the money there man. All mercs will use oil even the latest C63 AMG new from the showroom. My C36 AMG has it printed in the user manual that i should expect to see oil consumption at the rate of 1L+ per 1000km-1500km of hard driving.

And yes in the 24-head just like the 12-head of the M103 the main reason for increased oil consumption is the valve stem seals.
Mind you the 1989 and later M103 have better designed cams, guides and lifters. you cannot even use the new cam in an old engine unless you also change the lifters and rockers to the new ones.

__________________
Jay,
-----------------
-1995 Blue W202 C36 AMG (M) SOLD ;(
-1995 Black W140 S500 (Lady)
-1992 Black W124 E300 (Dima) (Ex-Mosselman
Twin turbo Kit).
-1988 Black W124 300 E 4-Matic.(Nadeen)
-1983 Brown W126 500SEL.(Old Lady)(Sold)
-1981 Gold W123 280CE.(Dareen)(Sold)
http://www.youtube.com/user/jayrasheed

So It would seem lean mixtures were the reason the rings cracked?

I believe it was not uncommon back then to use cast-iron for the second ring,with ductile iron on the top ring,cast iron is about half and strong as ductile and could possibly have been more affected by the extreme heat even though it wouldnt have seen as much heat as the top ring.

Are the rings widths 1.2,1.5 and 3? if so you could possibly just use replacement Mercedes or after market rings made for MB engines!.

Were the ring-lands ok on all pistons?,if so i would be sticking with the same pistons,just get new rings...i got new ones recently for mine(aftermarket MB) and they cost me $150nzd (~$75 euro)

^Paul is correct
see if you can get factory mercedes rings to fit, if not you may be able to get the pistons machined to fit a different ring size.

is your engine fitted with piston oil squirters? they are at the bottom of the cylinders above the crank pointing up at the pistons?

im sure m103 and m104 bottom ends are the same, and yea those pistons have got hot, either running lean or dear i say it detonating.

those pistons look like they've seen some heat
and the factory ecu like you say has the ability to retard ignition timing, but it only has limited ability, if it is running extremely lean and "knocking" it can only retard so much,

and jayrash i can imagine someone holding a engine wide open even if it is detonating because some people are idiots,

Yes the M104 CIS can only retard abt 6 deg of timing, so if there is serious detonation going on then yes it wont retard more than 6deg and the detonation will remain.

I really doubt slight ping will hurt the engine, i had driven my M103 in stock form ( not turbo charged, here konck will break it easy) with ping on every other top end run for 100s of thousands of klm and nothing ever went wrong. Mind you it was slight ping which u could hear come and go. if its more serious knock I’m sure it will break ring lands or rings. as for the 3.6 engine in question well if its knock that had broken the rings it must have been really serious knock to be able to slap the pistons around with the pistons almost at the lowest point in the cylinder were it has has the least side support and the lower rings would be hurt most.
Is my reasoning correct here???

__________________
Jay,
-----------------
-1995 Blue W202 C36 AMG (M) SOLD ;(
-1995 Black W140 S500 (Lady)
-1992 Black W124 E300 (Dima) (Ex-Mosselman
Twin turbo Kit).
-1988 Black W124 300 E 4-Matic.(Nadeen)
-1983 Brown W126 500SEL.(Old Lady)(Sold)
-1981 Gold W123 280CE.(Dareen)(Sold)
http://www.youtube.com/user/jayrasheed

To day I went to the shop to se some of the things and get a half conklusion on things.

First of all he had cleaned one of the pistons completely in the ultra sound bath wich you also normaly clean a cylinder head in.

And he said there where no purpel colour only balck. and that colour totaly wanished when he cleaned the piston, so he said there has been no hot isues at all and if it had run lean, he would have seen signs on the head combustion chamber as well, and this is in perfect condition.

So that made me a bit happy, and the KolbenSmith pistons are patent made specially to there purpose and in this case it is developed to this BRABUS 3.6-24 so that the reson for the price of 700 Euro for each pistons that only BRABUS can deliver
But that should be no problem to get else where now a days I was told.
But he could get me new rings if the pistons where ok, and the price for thouse would be 185 Euro each. that is an Ok price I think.
The worn out rings where not cast iron but the same as used to day with nikasil or something like that.
But my question remained about why it was only the lower compresion rings that had broken into piesces, but it might just be another material perhaps.

My engine has the oil sprayers that point up under the pistons.

But he said he would like to go and check the cndition of my cylinders, if they where stright or opened in the top.
This would make the pistons rings goes in and out, in and out ever time it move up and down, and this he said could have casued the broken rings, but he would have to measure that and it was anyway not likeliy, because then all the rings should have had the problem.
Hey another thing he said,,, even though all your oil rings and top compresion rings are intacted, they are all very slappy and this could be just a normal wear thing.
BRABUS confirmed this for me to day when they told me in an email that normaly the just replace the rings and reuses the pistons in most cases because that is always what wear out the first and the pistons and cylinders can easly take antoher round of 100.000 Km without any wear while the pistons rings are the thing to wear out 2 or 3 times before the engine needs new pistons or cylinders make over.

So I think im going in the right direction here, just get new rings and then im back in the game.

but again, just to make it 112% sure, he will check the tolerences of the cylinders as well as the pistons, but the pistons he said looks very fine.
And so does my cylinders I now but ok itīs better checking than being sorry when the new rings brake 2 days after because of to much tolerences between pistons and cylinders

The valves is also a bit special, but he had them in stock aven though they also are very hard to come by he said, but I will get a good priece he promised me.
He kind of like my projekt I think and he is a very nice gye who put all his work into finding me the right pieces and the right prices as well.

So my pistons seams fine and my spark plugs where also just showing signs of oil burning and not lean or hot isues.

So my best hope is that I will only need new rings and then a rebuilt on the head and then im going to play my 285 HP plus some extras

I will realy end up with a very fine engine to last at leastr 200.000 Km. without any isues at all if drove carefully before I again will need a new set of pistons rings or a head rebuilt

To day I got the Cylinders measured by the shop.

They were all in very good condition without any deformation at all.
They where 92,25mm to 92,29mm.

I guess this is ok then, because they are all this size, without any differences from bottom to the top all the way around inside the cylinder.

But is 0,09mm a fair play room or what is the standart tolerences?

Here some more pictures

Attached Thumbnails

         

Here some more pictures

Attached Thumbnails

         

Thats great news,thanks for the pics!
Interesting finish on the bores,there looks to be almost no crosshatch?.
Is that a standard crank?

You will need to get the recommended piston to wall clearance from brabus,or from the piston maker as the type of material useed to make the pistons will gauge what clearance you need,for example the MB high pressure cast pistons i use have a recommended clearance of around
0.8 thou,but if say you had a JE forged piston you wouldnt run much less than 3.5 thou. for comparison your 0.05mm = ~2.0 thousands of an inch.
if the bores are good and do not need much work than a deglaze and a set of new rings sounds like the way to go!.

when you reassmeble the engine be very very sure there is no dirt/dust/sand/metal shavings etc etc anywhere as it ends up in places like your intake cam advance,hydrolic lifters and main bearings...cam advance and lifters both are easily damaged by dirt and are very costly to repair or replace!.

Cheers,
Paul

Thank you

The pistons is forged aluminium pistons like the ones you see in a 2 stroke engine (it looks like)
The crank is also a BRABUS forged/steal and stroked crank.
The Stroke is 90mm. and i guess itīs coming from the 350SD W140.
But it could also be a BRABUS envented thing but im almost sure it is the crank from a 350SD W140. as also used by AMG.

The cylinders is very fine I think to, so I will defently just go with new rings

Can anyone clear this out for me on the top of the pistons is written 92,20mm, some people say that this is the pistons sizes, but some people say that this also could be the cylinder bore the pistons would fit in.

With my refurbished head with new valve seats and new valves and valve guides, planed and polished, then i Think im going to get around 300 HP. normaly it has 285HP and 382Nm. with the standart catalyst, but this has been exchanged from Carlsson to a dobbel metal catalyst wich is giving it the last HP to reach the 300 HP and 400Nm.
But yes I will clean all the engine before its put all togethre again.

The pistons I have seen have the bore size stamped on the top and the piston clearance. The clearance will follow the letters "SP".

Yes my cylinders was measured to 92,20mm (Bad measurement)
The pistons was measured to be 92,15mm with no wear at all. (Bad measurement)

On the top of my pistons is written the following:

92,20 and on the other side is written 0,05

So this is just great news, and I wil only need new rings, but they are a bit ekspensive. 190 Euro for each piston rings set. and I need 6 pc.
So it will be a total of 1140 Euro for a complete set of rings.

But that is better than needing all 6 new pistons or needing to re bore the cylinders

6 new pistons is 710 Euro for each piston. 4260 Euro total so im very happy that not was the case.

Hey!,
So the pistons can be reused,thats good news!.
As for the rings they sounds very very expensive,are they being supplied by brabus?...or are you going to use MB rings?

Also i see you mentioned replacing the valves...did they really need replacing?..or did you just replace the valve guide seals?.

Paul