Everyone who has ever had problems with engine blow up, please HELP.
What do you think about scratched CRANKSHAFT by connecting rod bearings. causing by LACK of engine oil. NOW i do polishing my crankshaft at
2mm and will go with first repair bearings from simple Crossfire not SRT as it does not provide any other bearings. And now all i am afraid of breaking to parts my crankshaft as it gong to be up to 2mm thiner after polishing. secondary i am afraid of bearings as whey are not going to be from AMG any more, just from serial c320 with 215hp, so they migth not be enough strong for the AMG model. If you have any Expiriance towards this just help.

 

Go to a machine shop and they will decide what is needed. Woody

Bearings dont decide the HP.

 

I agree get a machine shop that does this kind of work all the time and will give you the information you need, and after I went through the engine to repair it, (if you did it yourself) I would be more worried about spinning a rod or crank bearing because of the 2mm difference, but more important would be is why you had no oil there to begin with, and what caused it to have this problem ?

 

spinning a rod bearing from lack of oil would be my first concern...second, I would do as the others suggested...a good machine shop will match the bearings to the crank, and won't be a problem at all...has nothing to do with HP...but getting oil to them is most important...plugged holes, bad oil pump, low oil level....need to figure that out first....good luck...

 

Thanks, I did not repair engine my self it does work shop, i just wanted to know if it is ok to go with polished up to 2mm krankshaft and bearings that will not going to be from AMG manufacture as whey do not offer any bearings for repaired crankshaft.

 

Rasim
Crankshafts have hardened wear surfaces and the inner core of the material is much softer but stronger. If the crankshaft was hard all the way through it would soon snap into pieces.
I do not know the specific depth of the hardened surface on these crankshafts, normally it is only a fraction of a millimeter.
If Mercedes does not offer bearings for a reground crankshaft then I would assume that the crankshaft does not have enough depth of hardness to allow for grinding.
If the final hardening of the surface was nitriding or tuftriding then the surface would easily be all gone I think after .25 mm of grinding per face. If the engine only needs .10 mm of hardened material why add more?
In the old days you could regrind crankshafts, I think high performance engines these days require a new crankshaft.
When you mention polishing I think you mean grinding, 2 mm ( 1 mm per side) would have been too much for the old crankshafts.
You should check the truth of what I say but I am not too far wrong I think.
I'm sorry the news I give is not very good.

 

I check the information with my work shop an d i was wrong not 2mm (1 mm per side) and just only 0.02mm per side that means all grinding took not more than 0.05mm

 

there you go....that is more like it.....they just cleaned it up a bit...you should be fine...but, what caused the failure to begin with?

 

I'm glad to hear that news, the material you said was removed was excessive. Presumably the workshop removed enough material for a standard size bearing.
Good luck.

 

Rasim, is this on your V8 engine?