Board member AWE46M3 Rod-Bearings Service/Concept

[Anri]

Hi Gents,

Thought of sharing this.

I have a long list of services to perform on Nick's M3, some mini projects are boring but will
share the interesting stuff.

Nick had his bearings replaced pretty recently like ~1000 miles ago. Oil pan gasket
is leaking like a pig to a point he was afraid to drive the car to my shop...but he made it.

The bearing replacements were done with STD-Glyco OE bearings and they were sent out to
WPC treatment.

Attention. To each our own.

WPC has absolutely no benefits whatsoever from any point of view for bearings. I have proved
this times and times again. It's money spent in a very wrong direction. Its surface treatment
that has absolute no benefits in this specific application.

The best choice one can choose for bearings is Molybdenum Disulfide known as Moly or
Irox coating. They are similar.

S54 with its inline-6 platform the crank is subject to constant twists at hi revs. The factory original
clearance of 0.038mm is fine for lower revving engine concept. But not ideal choice for 8000rpm and
up..because when the crankshaft twist it will reduce the oil clearance at the edges. Please note at
~1000miles how the bearings are worn out at the edges where the crank has been twisting.

The best choice for high revving engines and what it has been working for me on S14/S38/S54/S65/S85 etc
hi revving platform is bearings with Moly with increased oil film. This concept is for longevity and keeping the
rods in the block. Not rods shooting holes thru the block.

It is thru that tight tolerances will produce tiny more HP, on NASCAR engines the bearing clearances are very
tight, and they run thin oil. Well after 500-1000 miles with 9000rpm the bearings will require replacement for sure.
(race engine maintenance)

So, I will trade 2hp at 9000rpm for longevity and 2hp less at 9000rpm

My #1 choice of bearing is ACL HX with increased clearance. From that point on I prep the bearings for Moly coating.

The HX ACL bearings on std not polished S54 crank is 0.051mm. My target with Moly coating not less than 0.051mm,
in this instance I ended up with 0.055mm. Have been doing the moly coating for a long time and I have mastered this
process.

I have tried every possible concept of lubricant to dress parts during engine build in various areas. In this area
I use Driven hi preassure assembly line grease for the bearings. Before one comments about the feel on turning
the parts one can assemble with let say 0W20 and check how the parts will turn and then disassemble and use
the Driven high pressure grease. In this case were we know the engine is running perfect no need to perform a test.
So directly Driven is used. The oil pump is also apart for inspection, after start the initial oil pressure build up will be
longer than normal.

During rod bearing replacement the spark plugs are out so that the grease will not be completely squeezed
due to building unwanted combustion pressure during turning the crank.


Moving forward.


Regards,
Anri








1000miles



1000 miles

[0-60motorsports]

Awesome! How much do you sell the bearings with the coating for? Message me if thats better. Thanks.

[bmwfnatic]

Awesome! How much do you sell the bearings with the coating for? Message me if thats better. Thanks.

I’ll take a set too, for science 🫣

[Anri]

for science 🫣

I have done it years back in multiple engine inspections.

The pictures bellow is coated bearing from rebuild S38 engine.
After complete rebuild, engine completed around 1500miles
with tuning time on a Dyno and endless pulls to the red line
of 7800rpm.

(The miles covered were just as much as this WPC in NIck's S54 engine, the
difference is obvious.)

Right at around 1500miles the S38 Engine established low pressure build up on a cold start
meaning the light would stay around 10sec on....waay too long...and light on
low oil pressure at 0.3Bar when the oil gets hot from around 2000rpm>1000rpm
(problem was failing filter housing oil pressure valve)

I got New S38 ACL-HX bearings coated them and I was ready to replace them, main
and rod. I dropped the pan and to my surprise I sow no damages, no scuffing, no scoring.
Checked the clearance all good and put the cap back in and engine keeps counting miles
and miles.


Its not that the OEM set up its not going work, std 0.038mm bering clearance, not hardened
bearings shells as the ACL are, its fine. But it will never ever be the concept I am using and one
can see it as proof. I am after OEM-Plus.

I never intend the coated bearings for sale online. I only do them when service rod bearing to customers.
I may make a small batch and can do 2 additional sets..will see.



S38 (low oil pressure)















Note: If a crankshaft has micro scoring as in the picture bellow it is not good and no matter what
it will slowly damage the bearing. With Moly coating it will survive longer time but eventual it will
take it off.. It does not matter that if you run your nail it will not be felt...








Moving forward.


Regards
Anri

[nextelbuddy]

This is good information to know. My red s54 turbo car has WPC treated BMW bearings have about 12,000 mi on them over the last 4 years.

My s54 wagon recently when I did my rebuild I used ACL standard bearings. I gave the bearings to my local engine builder who is an old school guy. He was the chief engineer guy for the panos team Back in the I want to say late '90s early 2000s. Really cool guy with loads of stories and pictures from back in the day

He took the ACL bearings and he applied a moly based coating to them.

[Anri]

My red s54 turbo car has WPC treated BMW bearings have about 12,000 mi on them over the last 4 years.

The WPC has virtually no benefits what so ever for bearings.

I gave the bearings to my local engine builder who is an old school guy. He was the chief engineer guy for the panos team Back in the I want to say late '90s early 2000s. Really cool guy with loads of stories and pictures from back in the day

He took the ACL bearings and he applied a moly based coating to them.

This is good.

But here is where he should have improved. The STD ACL bearings clearance is 0.038mm
exact like the OEM. When you apply the coating you are tightening the clearance down to around
~0.030mm +/- and that is not good at all! Because from the S54 Hi revs the crankshaft is twisting
at the end of the bearings and it will scrape the Moly away in no time. And then wrong conclusions
are made.



The proper way is to take ACL-HX with additional clearance and with the Moly coating
one must be min 0.050-0.055mm as seen in the pic above. When I media blast during prep
the clearance is around 0.055mm then the moly tights the clearance down to around ~0.051mm.+/-

Regards,
Anri

[bmwfnatic]

~

Anri, what is your take on why the M engines have rod bearing wear at all?

For me it’s always so random, some engines at 150k+ miles on the original bearings and they look fine. Others have been replaced 50k ago and they are entirely down to the copper layer again.

Also what is your take on the original main bearing clearance, would love to know.

[sapote]

Note: If a crankshaft has micro scoring as in the picture bellow it is not good and no matter what
it will slowly damage the bearing. With Moly coating it will survive longer time but eventual it will
take it off.. It does not matter that if you run your nail it will not be felt...

They say the crank journals don't touch the bearings, so why a micro scoring will eat the bearings soon? From cold dried oil engine starts?
Yes, the journals should be mirror polished.

[Tbonem3]

I say just do oe nothing else and call it a day. Are you reslly doing another 150k at this point?

[Anri]

They say the crank journals don't touch the bearings

Obviously, ones the oil pressure is build the journal does not touch the bearing. its been
like that since combustion engines are around...

so why a micro scoring will eat the bearings soon? From cold dried oil engine starts?

That is correct, micro scoring establishes when cars are not driven often meaning say ones a month
sort of how collectable cars are. By the time the oil builds solid film little at a time it causes micro scoring.

Cars in cold climates with the combination of the 10W60 are the worst combo. This is why I like 5W50
0W50, 5W40 oils. 10W60 is way too thick in cold climate or long term storage dry start.


Regards,
Anri

[Anri]

I say just do oe nothing else and call it a day. Are you reslly doing another 150k at this point?

OE was inside, did you read post #1 ?

Idea is to save the crankshaft journals. So "call it a day" now but cry later when the crank
gets slowly damaged beyond polishing option....and then New crank must be sourced.

I will check Compression but I see no problem with easy 80-100k miles on top of what he
has now. S54 is very rigid engine, just need little love and they will last very long.

[Anri]

OEM-Plus, Street/Race

The oil pressure on the S54 in general is on a low side per my liking.
I believe in higher oil pressure in the system for longevity. I can show the entire
oiling path on the S54 but it will take a very long post with pictures, measurements
it is time consuming and now I am limited on time.

The S54 at hi revs with the std oil pump rotor the peak pressure/spring is around
~4.5Bars it depends on oil viscosity using 10W60, at the track with outside temps
of around 100F, I have seen 4Bar peak at 8000rpm.

I have done dozen hi-volume oil pumps and with the combination of bearings with
more clearance it work great.

Benefits from the Hi-Volume oil pump:

- Without losing pressure in the system, the oil flows thru the bearings faster with the
increased clearance of 0.055mm and it takes the heat away and keeps the shells cooler,
critical not to over heat the shells.
- One can run thiner oil like 5W50, 0W50, 5W40 to benefit cold start and rapid engine acceleration.
- More oil volume in the head/rockers
- Overall higher oil pressure
- At the same temp at the track let say 280F on the oil the larger rotor will be maintaining higher
oil pressure using the same viscosity/brand oil vs stock rotor.


Almost every E46M3 Rod bearing service I have performed I have installed the hi-volume oil
pump. If one is interest contact me. It works with a core exchange.


Moving forward

Regards,
Anri

[Anri]

Cold-Climate-Cars.


Being around California cars and also have worked on tons of
cold climate cars. Cold climate cars/engines will have more
sludge than hot climate cars driven the same milage.

This oil pan hit the record so far I have seen on sludge build
up. Most foxes when see so much dirt sludge build up are like "f...that"
close it back together as-is..

The sludge was so hard that my big ultra sonic cleaner did nothing...
I hot tanked it and it did help tiny bit but far away from how it turned out.
I had to complete the final touch using my methods and chemicals.

[Anri]

Not surprised to see individuals use Silicon in/on engines.

The most ridiculous place I found silicone is mind boggling,
it was on M88/3 inside the radiator fins...due to the individual used
silicon on the Water pump....complain from my custom was that the
engine runs hot all the time...

Excessive amount of silicone can be found in the oil pan Screen. Not
proper oil pan screen to pick up tube assemble sequence resulting
bend ends.

[bmwfnatic]

~

This is nothing in terms of silicone, I have dissassembled an S54 once where every single gasket seemed to have a tube of the stuff added to it, from oil filter housing to oil pan, water pump, everywhere. I had a whole pile of ropes of the stuff after I had the entire engine apart...