Saving a S54 From Parting Out.

[Anri]

Coating piston skirt and coating bearings is std
in my builds.

Regards,
Anri

[Anri]

For the last 10-15engines I started doing Molybdenum skirt coating
in-house mandatory on my std engine rebuild/s. Its either to restore
the S54 OEM or aftermarket unless they are ordered with.
Many good benefits to be had.


Moving forward.


Regards,
Anri

[Anri]

Anri,
I believe you have found the root cause of the gasket eating problem: engine high temperature due to cooling channels blockage.
The question is how to heat sink the multiple stacked gaskets to offset the 0.021” machined block, in order to keep the gaskets eating monster away.

Sapote,

The blockage was not the primary reason but certainly does not help.

The main reason as I mentioned above is the fact that the left over impeller
count like may be 2max I don't have the broken water pump infront
of me but I found 2 impeller pieces in the engine block and 1 in the head.

So from total of 5 blades only 2 left! At 2 the water flow is disaster and with
the combination of the 2Bar cap to keep the cooling system under hi pressure
in order to raise the boiling point makes the water move slow to almost none
and this is the pure evidence why the engine suffered maaaaasive overheat but
with water inside. I'm sure that the pressure exceeded 2Bars and the expansion
tank was releasing/splashing coolant but the engine never lost water.

When I put the head to inspect it as-is the natural warpage was nearly none!
I don't remember already but it was 1-2thou across...which gives me the indication
that the engine never lost water/coolant, or otherwise the head warpage would
have been far more than what I found.

Shortly I will compare the water pump and why S54/M3 owners should NEVER
use any other water pump than OEM.


Regards,
Anri

[Anri]

Short skirt piston like.

Far more important to say is the lower 1.52 Rod Ratio which is very bad
for the piston trying to cock the cyl wall. On top add the short skirt.

But this proves that if you do coating and the groves there is no problem at all..

On S38 B35 with Connecting Rod ratio of 1.71 (were S54 will only dream to get)
the damn skirts have scores on the exhaust side...and less on the intake.

S38 pistons have no coating, and the groves are Coarse and the reason to get
scored.

Regards,
Anri

[sapote]

Anri,
I believe you have found the root cause of the gasket eating problem: engine high temperature due to cooling channels blockage.
The question is how to heat sink the multiple stacked gaskets to offset the 0.021” machined block, in order to keep the gaskets eating monster away.

[sapote]

Short skirt piston like S54 tends to have more wear due to higher rubbing force.
You are right that the grooves around the piston retain oil and helps.

[Anri]

Clean parts and clean assembly is a must providing the best service to customers.

[Anri]

Sapote,

Great work, Anri.
Q: The high temperature and pressure gas leaked and cut through the cast iron wall between the cylinders, but why it didn’t cut through the softer walls on the head (except one with a hair line crack)?

Remember the cylinder bores are Siamese on S54 engine and the heat is concentrated exactly in that spot.
That material is way hotter than the one on the head were the water sits. Its also the reason why when BMW increased
the bore from (S50B32 Euro at 86.4mm) up to 87mm they had to move to MLS gasket and single solution to
survive the increased heat and even then from age (not damage such overheating etc) they get tired and its time for
service. S5032 never burns gasket in this way in-between the bores. Its never common problem on them,
the older BMW engines the problem is corrosion on the gasket which leads to failure.[/QUOTE]

It is amazing that the old pistons have almost no wear on the side and skirt from touching the cylinder wall. How?

Answer: There are 2 main reasons.

A) Primary key/reason is the OEM pistons do have Graphite coating from new !!!!
B) If you pay attention the side skirts on S54 pistons the lines/groves are very deep and that is very good thing because
retains oil !!! If you take any aftermarket pistons they have those Coarse if I can use this word?, groves/lines.
At last is the expansion rates are very well calculated, I have never ever heard piston slap on S54s engines. Take
an older S38, S14, M30 etc...they have massive piston slap on cold start till they warm up.

The graphite coating+deep groves= to a absolute great lubrication operation and with the great hone from the factory
is the Engineering answer behind your question.[/QUOTE]

Any measurable on the ring lands by the rings?

I work from ages on S38/S14/S54 and have not seen single one with worn out lands, at least the ones I worked
on rebuild re-using the OEM pistons. This is not subject of ware out area.


Moving forward.

Regards
Anri

[tlow98]

Great work, Anri.
Q: The high temperature and pressure gas leaked and cut through the cast iron wall between the cylinders, but why it didn’t cut through the softer walls on the head (except one with a hair line crack)?

It is amazing that the old pistons have almost no wear on the side and skirt from touching the cylinder wall. How?

Any measurable on the ring lands by the rings?

I was shocked by the lack of wear on my 212k mile motor. The pistons spec’d out to exactly like new. Within the tolerance of a new piston. Every one. I have no idea how. The rings lands were the same.

the bores had opened up slightly, but only ~20% of total allowable wear. The rings were at double the bmw spec. They seemed to be the sacrificial anode.

[sapote]

Great work, Anri.
Q: The high temperature and pressure gas leaked and cut through the cast iron wall between the cylinders, but why it didn’t cut through the softer walls on the head (except one with a hair line crack)?

It is amazing that the old pistons have almost no wear on the side and skirt from touching the cylinder wall. How?

Any measurable on the ring lands by the rings?

[Anri]

Again, clean parts and assembly is crucial when I assemble
engine.


A lot/most people have absolute no clue how much time it takes
to clean the parts to a level of how you see it in the pictures.


AquaBlast is knife with 2 edges, it is very physical work when one
is after to clean the engine parts. If cleaning crankshaft main cover is not
a big deal but when you start spending 1 2 3 hours my hand gets
sore because the gloves are hard and the Hi pressure requires
lot of muscle work out. Parts like the cylinder head It takes around
2 hours to clean, wash after its done and dry.

Moving forward.

Regards,
Anri

[Anri]

The OEM pistons are still in spec. Cyl number 2 piston is replaced with a good one I
have exactly for this kind of situation/s and needs replacement of 1. The new/old
piston is totally in spec.

Every engine I rebuild re-using the OEM pistons with New rings like in this case
I make sure there is not a dot of carbon build-up left anywhere. Few months ago
I started using Aqua-Blast method cleaning parts. I am tired of the old school
rub-rub with a brush in parts washer...

In the picture on the far left is S54 piston, middle is S38-B35, and far right is S14
pistons being cleaned up for current on going engine rebuilds.

It is critically important to clean the ring land areas to be absolute free of dirt,
carbon etc...Each ring land has been closely inspected for potential cracks
after being completely cleaned up.

[Anri]

Today's day was nearly ruined.....the composite water
pump piece was stuck hard in between the casting as
can be seen in the picture above.

I started very gently to push the piece but it was not
moving at all. Tried many approaches and was still
not moving, then increase the pressure and all of
a sudden the piece unlocked and ran on me inside
further in the cylinder head and completely got lost.

Then put grease on the seats again and back in the
water bath container. The container is just as big as
the cylinder head filled up with water all the way up
and started to pull the head from the water up in the air
so that the water drains from the head. After I repeated
this several times the piece came out from the Back
tapered water plug.

It felt very good to see the piece came out. I went with my
bore scope camera and checked the rest and seems
its now finally all clean.

Moving forward.

Regadrs,
Anri

[tlow98]

Wow. That’s a bunch of stuff. Thanks for the tips on the oil passageway cleaning.

sry to see those cracks in the heads.

The lesson I’m seeing here (and that I learned first hand) is that all used s54s are not equal. The block/head interface is sensitive to blown HGs and delaying that repair incurs a ton of extra time, expense, and engjne build changes.

what HG will you use on this build?

[Anri]

Were is this going to stop?.....Its one surprise after
another...When I meant from parting out I really meant from
parting out !!! sapote cylinder head is aluminum and
welding a crack is a common practice.

Okay, so the block is now done and on the engine stand
ready to assemble.

After the block was finished I moved to skim the head

I set the head on the stand, put the marker paint and made
a micro pass to inspect if the head is set on the table flat, it
checked like 0.000002mm lol...which is totally fine.

Then set the machine to make my 1st pass at 3thousand-0.076mm,
Ran a pass and what do I see....fucking hidden micro cranks
were the compression was crossing back and forth.....fuck is
what I said loud.

I called local Hot-Rodder chassis fabricator who welds on
daily bases.

He came and ground the cracked area like ~8mm deep in
Arc but in flipped upside down orientation. He welded a bead then
stopped and started forging it with small hummer with half a moon
shape. Ones he forged the bead he started to weld on top and add
material and repeat the process 3-4 times.

Ones he was done then back on the decking machine. With the
welded areas I ended taking 7-8" thou or ~0.18mm which is
not that bad for what I am dealing with.


Regards,
Anri