While I had some of these cranks out and souring newe parts, thought I would show how AMG sets up there bearings.

Each block is color coded and stamped on the block near the main journal bolt holes. Most the blocks I have seen are yellow coded or #2 stamp bearing shell size. That takes care of the block side but the main caps can be one of about 5 colors or sizes. The way to tell how your block was set up, you remove crank and pull cam gear off and you can read the color code on marked on the crank. R is for red and W is for white. There is blue, yellow and violet as well.

Still best to check the tolerances, as AMG has them on the tight side for the power most of our making or plan to make. Also a sleeved block should be checked as well, as sleeving can move things some.

 

Good info. Thanks Brooke!

 

Thanks for the code info, so the colors are oversize/undersize codes when using factory bearings? Do all the cranks have that info on them? I don't recall seeing that on the last one I tore down.
Factory clearances are very tight on these engines, hence the thin engine oil. The mains you can leave on the tighter side .0012-.0016 is ok, because the block will expand a little when it's hot. The rods need to be opened way up, as in doubled. Don't run less than .0025 clearance on an engine that's going to see a lot of torque/rpm.
Have you guys got any MID blocks running yet?

 

Mitsubishi has been doing this for quite some time as well. Good to know for the MB though. Thanks for sharing.

Aaron

 

Numbers are stamped on all the cranks I have tore apart (about 11 engines) but you have to pull the cam gear off to see it. The R or red color code is about in the middle of the bearings mb offers but even their looser size (Violet) is still pretty tight. The O is for the thrust bearings and there are two sizes offered. Best is to polish the crank to the size you want for now, until we all have time to get the 5 dollar honda bearings lined out to fit. .

We are building 5 darton MID engines at the moment and two are getting close but waiting on pistons.

WHTEVO, yes Nissan uses the same set up as well.

 

40W is not a "thin oil" in my book...

 

I agree, straight 40W weight is not a thin oil.

 

Which engine is this?

For what it's worth, those are some hella tight tolerances. A lot of engines run. 002-.006".

 

A 0-40W is the same as a straight 40W once the oil has reached operating temperature , so a 0-40W should not be considered a thin oil ...

 

That's a good one

 

The info I posted is for the 55K motors (E55, S55, CL55, CLs55 , etc with kompressor).


Here are some more detailed color codes and tolerances for the mains.. As you can see, even from one range to the next, not much of a change in clearances. The crank in our cars is first class and the machining used is also damn nice but as mentioned, if you want to add a lot more TQ and HP, then more tolerance will be needed. Depending on your bearing code , you have a few choices to help get you in the right direction. If anything is to loose, then bearings can be coated as well. Not many options for rod bearings but to size journals to set tolerances, based on what MB offers.

 

Nothing resembling a street car is going to have clearances nnywhere near .006
You could carve your own crank from a solid block with a chisel and get tighter tolerances than that. Also fwiw if you use the adjective hella to describe anything the context often is regarded as nonsense

There's some awesome choices for rod bearings, any have nothing to do with Honda shells or whatnot. Stay tuned

 

Do you know MB's numeric designation? Like the engine in my E55 is an M113.
Wow! Those are some very tight tolerances indeed!
I'd be scared to use anything with .001-.002" clearance in any sort of sustained high RPM use. But then again, I'm fairly new to the MB scene. Most American V8's would seize up if they only had .001-.002" of clearance.

Funny, that's the correct answer on the certification test.

Also, tolerances are dependent on the intended oil used in said engine. In most racing applications (not talking drag cars here), they use 20w50, so their tolerances are as high as .008". But this too is dependent on the engine, heat dissipation, etc.etc.

Tighter tolerances aren't always a good thing.

I think you're hella wrong about that..

 

The supercharged engines just add a K on the end to indicate being supercharged. So M113K is the 5.5 supercharged.

If you're referring to an ASE test, please disregard anything you saw on that, it's bout as useful as having a certificate in PASCAL programming and equally as relevant to 2013 vehicles.

I'm asuming you're young, so I'll try and help you out. American V8s do run clearances in the .001-.002 range. Closer to .001 on most main journals to account for aluminum block thermal properties, unless you're talking about old Triassic era stuff like a 350 Chevy or an old Hemi. For instance the mains on a 2013 Z06 7.0l are .0008-.0012 spec from Gandean 7000 rpm and pass 200,000 durability testing. The machining tolerances were much more relaxed back in the day then so the clearances were loose in comparison.


If you were to try and run a modern gasoline engine with .008 oil clearance you'ld have to run roofing tar for oil to keep the crank from beating the bearing into tin foil. feel me dawg that's hella loose

 

With all the tolerance debate going on, dont forget that tolerances should be set up for journal diameter , so with that philosophy, depending on the engine journal size, the tolerances would vary from say a 63mm journal to a 80mm journal. Some use .001 per inch of journal diameter amd other have different philosophies.

These M113K engines have a pretty neat oiling system and return oil flow VS say most American engines or LSX engines.

 

Old thread but that doesn’t make any of this information any less useful or pertinent..

recently I was very interested to tear down a m113 55 n/a motor from a 2002 cl55 recently to find no stamping on the nose of the crank, indicating which bearings are needed. Luckily the top side bearing is stamped into the block (every top side I have seen so far has called for yellows) but there is a color stamping on the side of the crank bearings to tell you which color you need, unfortunately my color standings also faded away after almost 20 years lol

the same technical documents I’ve seen throughout this thread also imply that you should be able to find the stamping on the nose of the crank in any 113 engine

some more fun info, when the 113k crank bearings are unavailable you can use the normal 112/113 bearings in a pinch, I compared them side by side, the main difference is the K bearings seem to be made of a slightly different alloy. On a digital scale, a pair of K bearings weighs about 69 grams, where the comparable 112 bearings weigh about 65 grams. There is also a noticeable difference in the coating used on the K bearings, it’s dull but seems to scratch off quite easily even with just a fingernail, I think this coating may just be for break-in? Not too sure

parts catalog for my 55 n/a amg motor actually tells me to use the aforementioned 112 bearings, and my old bearings even after 20 years of abuse looked quite great, more than one person told me they were fine to re-use in my rebuild but I ended up spending over $600 even with employee discount to get new m113k crank bearings and rod bearings just for peace of mind. My rebuild involves m113k rods and pistons because after examination they are structurally stronger than the high compression 55 n/a rods and pistons I originally had. I have photos saved somewhere in my phone or on my m113 build thread of the comparison of rod/piston dimension differences if anyone is interested

 

Sorry for hijacking another thread

On the crankshaft of my m113k (113.990) are NO markings...

Are there batches of unmarked crankshafts from the factory?

BTW my block is stamped 2-2-3-2-2 ...



best regards

 

yes I’ve noticed this before