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You can change the rod bearings as many times as you like but without checking the oil pump and relief valve you could be wasting your time and money
It least fit an oil pressure gauge
On start up these engines with 10/60w produce far to much oil pressure so this in part is where the warm the engine up comes from
At the weekend I will try and remember and make a video of the start up and warm up times, pressures and tempretures

PDJ wrote: ↑Tue Mar 30, 2021 8:39 am You can change the rod bearings as many times as you like but without checking the oil pump and relief valve you could be wasting your time and money
It least fit an oil pressure gauge
On start up these engines with 10/60w produce far to much oil pressure so this in part is where the warm the engine up comes from
At the weekend I will try and remember and make a video of the start up and warm up times, pressures and tempretures

Would imagine most indy's doing the job will give the oil pump a once over as it's out during the job anyway. Fitting an oil pressure gauge is a good idea but lets be honest a lot of people aren't going to want to cut a hole in their OE interior to fit a gauge or delete their air vents to do so. Track car, different story of course. Would like to do it on mine though discreetly, something to look into...

Interesting to see in the future as mileage goes up if there are more oil pump failures as there aren't many documented one's so far, certainly not enough to be too worried about it IMO.

AndyBeech wrote: ↑Tue Mar 30, 2021 12:51 pm
Interesting to see in the future as mileage goes up if there are more oil pump failures as there aren't many documented one's so far, certainly not enough to be too worried about it IMO.

It's not an oil pump failure, its the regulator piston wearing.
And it's a common phenomenon. Most indies don't look at this as they don't know, its mainly a problem known in the german community (they are as usual way ahead of the rest of the world).
Search the german forums for lots of well documented cases.
It looks like this:


As for what kind of potential consequential damage the worn piston has one can only guess. But that's the case with lots of things found in engines.

Anything to prevent that spun bearing breaking the conrod and punching a hole in the block right

I know that they make DLC coated ones in Germany specifically for the s50/s54. BMW doesnt sell this part seperately for the s54. For the m54 it's no problem (15quid part) but I think that one's different.

Thats sort of what mine looked like the pump was like new, but as it is all one part number the choice is new pump or blank it off and fit an external one.

Simon Thorpe ran a customer race engine for 20 mins on a test day and it went bang the piston had stuck giving no oil pressure, so it just by passed the engine and returned to the sump.

All his race engines now have an external relief valve and an oil pressure gauge.

GuidoK wrote: ↑Tue Mar 30, 2021 2:17 pm Fitting an oil pressure gauge is a good idea but lets be honest a lot of people aren't going to want to cut a hole in their OE interior to fit a gauge or delete their air vents to do so.

I would rather loose an air vent than my engine
I kept the original centre vent so it could be re fitted if required, just blanked the vent off inside the dash.

GuidoK wrote: ↑Tue Mar 30, 2021 2:17 pm

AndyBeech wrote: ↑Tue Mar 30, 2021 12:51 pm
Interesting to see in the future as mileage goes up if there are more oil pump failures as there aren't many documented one's so far, certainly not enough to be too worried about it IMO.

It's not an oil pump failure, its the regulator piston wearing.
And it's a common phenomenon. Most indies don't look at this as they don't know, its mainly a problem known in the german community (they are as usual way ahead of the rest of the world).
Search the german forums for lots of well documented cases.

Hmmmm, not sure I entirely buy that. The engine is what, nearly 20 years old, and all the other experts in their field across the world aren't shouting about it and using it an an opportunity to sell yet more expensive aftermarket goods...only Germany are? I'm sure what your saying is correct across German forums but something doesn't quite add up for me. I'm sure the Germans aren't the only ones to have stripped down many an S54 engine and look into the deeper workings / problems.
I'm still talking in the realms of the everyday S54 driver here by the way, not one's built to race or purely track weapons. In that case yes, I would be looking more into it for sure and would probably just buy a new pump.

AndyBeech wrote: ↑Tue Mar 30, 2021 7:51 pm
Hmmmm, not sure I entirely buy that. The engine is what, nearly 20 years old, and all the other experts in their field across the world aren't shouting about it and using it an an opportunity to sell yet more expensive aftermarket goods...only Germany are? I'm sure what your saying is correct across German forums but something doesn't quite add up for me

It's a fact that you find these worn pistons all over the german forums and not (yet?) on say US or english forums.
So either this is an effect that is highly localized within boundries of a country, or germans mostly talk to other germans and they just dig a little deeper.
That these pistons show effect of wear is a fact, the pictures are proof.
And that there is a very competent german posse that roots around in these cars looking for ways to fix things is well known.
For example the sticky steering issue. That was also figured out on german forums (where yanks started to drill holes and fill them with grease the germans looked at how the column worked and started adjusting the ring). Who do you think was the first one to tell about this solution on this forum?
Just like relocating the roof pump, that was also done first in germany.
So why don't you believe that they wouldn't be competent enough to fix or discover yet another thing?

You believe what you want, without scouring the german forums.
This advice came free, you do what you want with it.

BTW a new pump costs about £650,- , that DLC coated piston about £80, so I don't get your remark about "expensive" aftermarket goods.
One can save money with these things, just like, say, fitting a set of vanos rings (or turning the adjustment ring on the electrical steering column) That's why people look at these things.
In germany lots of specialists offer to fit a new pressure piston at the same time when doing rodbearings. For like £100 more. (having rodbearings done in Germany is I believe cheaper anyway than in the UK or US judging by prices I read, but that can vary of course)

When you are plastigauging the big end shells do you need to stretch the rod bolts to do it so you need a new set each time?

GuidoK wrote: ↑Tue Mar 30, 2021 8:24 pm

AndyBeech wrote: ↑Tue Mar 30, 2021 7:51 pm
Hmmmm, not sure I entirely buy that. The engine is what, nearly 20 years old, and all the other experts in their field across the world aren't shouting about it and using it an an opportunity to sell yet more expensive aftermarket goods...only Germany are? I'm sure what your saying is correct across German forums but something doesn't quite add up for me

It's a fact that you find these worn pistons all over the german forums and not (yet?) on say US or english forums.
So either this is an effect that is highly localized within boundries of a country, or germans mostly talk to other germans and they just dig a little deeper.
That these pistons show effect of wear is a fact, the pictures are proof.
And that there is a very competent german posse that roots around in these cars looking for ways to fix things is well known.
For example the sticky steering issue. That was also figured out on german forums (where yanks started to drill holes and fill them with grease the germans looked at how the column worked and started adjusting the ring). Who do you think was the first one to tell about this solution on this forum?
Just like relocating the roof pump, that was also done first in germany.
So why don't you believe that they wouldn't be competent enough to fix or discover yet another thing?

You believe what you want, without scouring the german forums.
This advice came free, you do what you want with it.

BTW a new pump costs about £650,- , that DLC coated piston about £80, so I don't get your remark about "expensive" aftermarket goods.
One can save money with these things, just like, say, fitting a set of vanos rings (or turning the adjustment ring on the electrical steering column) That's why people look at these things.
In germany lots of specialists offer to fit a new pressure piston at the same time when doing rodbearings. For like £100 more. (having rodbearings done in Germany is I believe cheaper anyway than in the UK or US judging by prices I read, but that can vary of course)

No need to be huffy about it Guido, my opinion differs from yours, I know you don't take well to that but it's just a discussion (yes I have seen some of your other disagreements on other forums). I know you have a lot of knowledge, far more than myself but we're allowed to question things.

I'm not going to trawl through German forums no, I don't have the time to be honest and the translator on Chrome is a pain to use, so like I said I'll take your word for what your saying in that respect and I'm not doubting it.

When did I doubt the competence of German's? I'm just saying I don't believe there aren't other companies that haven't looked at it and not come up with a solution if it's as easy and cheap as you say and such a big issue? Is everyone else outside of Germany incompetent? Seems like an easy win (profit) for companies to bolt that on to a rod bearing change if that's the case, I probably would have done it myself if it was offered.

What I meant about expensive aftermarket goods is there are lots of bits and pieces out there that are offered for problems that rarely happen (I'm talking about all makes of cars here). So why would a part that genuinely is a problem as you say not offered? It's just my logic, not saying you are right or wrong.
Do you have a link to where you can buy these pressure pistons in Germany?

Who came up with the VANOS fix(s) by the way? First I heard of it was the Besian kit but presume that was the German's then? (Not being facetious, genuinely wondering).

AndyBeech wrote: ↑Tue Mar 30, 2021 8:59 pm and such a big issue?

I'm not saying its a big issue. I don't know the scope of the issue.
All I know is that these parts wear. You can see that for yourself. Lots of pictures to be found, all similar to the one I posted.

I'm not going to trawl through German forums no, I don't have the time to be honest and the translator on Chrome is a pain to use,

Learning a new language is a virtue

Is everyone else outside of Germany incompetent?

I'm not saying that everyone else outside germany is incompetent, those are your words. I'm saying that the germans are competent and sometimes come with very good solutions, better than the rest of the world came up with until that point.
But vice versa also happens: Beisan sold vanos rings for years and years until others also started to sell them. So by your reasoning, vanos rings were not an issue during that time because only beisan sold them.
Do you understand where your logic doesn't work? There is always a first one that finds a problem and a solution.
Will others offer the same solution in time? I don't know, there are still problems in these cars were ony 1 company offers a solution.
Doesn't mean its therefore not an issue. There is always the solution of swapping out the complete part. That has been done for years with steering columns (£2000), vanos units (£700 for the m54, £2.5k for the s54), damaged roof pumps (£250)(yes you can now get the separate motor), disa valves etc etc,
Fabricating and marketing parts to fix these parts I think isn't the gold mine you think it is.
Having a piston made (I believe they make it from stainless steel) and having it DLC coated for €80 (incl vat) isn't that much money.
They're not gonna sell thousands and thousands of them.

So why would a part that genuinely is a problem as you say not offered? It's just my logic, not saying you are right or wrong.

BMW doesnt offer vanos rings. And yet it's a problem (I assume you don't deny that....). BMW would rather sell vanos units.
Also easier to just swap out the part as mechanics have to be trained in everything.
Just as they only sell new starters, new alternators etc. Yet they are realtively easy to overhaul.
In general there's a trend to offer less and less individual parts and only swap out complete 'units'. That trend has been going on since the late 80's early 90's. You can see that also in the parts catalog. Why doesn't BMW offer diff bearings anymore and only swaps out complete diffs? (roughly since late e36/begin e46 era for example)

It's moving into nit-picking territory now....

I'm not saying that everyone else outside germany is incompetent, those are your words.

Not my 'words', it was a question directed at you to get clarity as to *me* you seemed to be inferring it somewhat from what you were saying. You weren't so, ok. Wasn't really my point anyway.

Do you understand where your logic doesn't work?

Not really no. The VANOS issue came about and was solved years ago presumably due to failures. As I mentioned originally, these engines are 20 years old now....and use a similar design oil pump to the E36 M3 so even longer than that in some respects. All I'm asking is why hasn't someone else seen the problem and decided to sell a solution round these parts or the US, which there is no definitive answer as we've established so again, ok. I guess my frustration is more that there's nothing I can really do with your information / advice as there is no apparent solution in this country yet...unless you go to JC who have a custom fix.

They're not gonna sell thousends and thousends of them.

Maybe not but if you tell people about it when changing the bearings I can imagine most people would agree to have it done.

I don't think selling some aftermarket parts is a gold mine at all, but profit is profit same as any product sold there will be a reasonable mark up. I'll run it past Ben at Hack next time I see him on a Q&A, see if he knows anything about a solution.

BMW doesnt offer vanos rings. And yet it's a problem (I assume you don't deny that....). BMW would rather sell vanos units.
Also easier to just swap out the part as mechanics have to be trained in everything.
Just as they only sell new starters, new alternators etc. Yet they are realtively easy to overhaul.
In general there's a trend to offer less and less individual parts and only swap out complete 'units'. That trend has been going on since the late 80's early 90's. You can see that also in the parts catalog. Why doens't BMW offer diff bearings anymore and only swaps out complete diffs? (roughly since late e36/begin e46 era for example)

Don't see this as being relevant. I wasn't talking about BMW. But yes I agree with what your saying there.

At the end of the day I hear what you're saying and I see the pictures and I don't disagree, but we're just trading arguments for the sake of it now with no advancement in the actual topic so I'll leave it there for my part.

If you have a link to the part from Germany though please post it up, I'd be interested to take a look.

I don't have a current link (don't have an s54 engine ).
I once made a post on Zpost about this topic, and linked to a Facebook topic from some tuner that sold them but apparantly that link doesn't work anymore? (not familiar with facebook policy)
https://www.zpost.com/forums/showpost.p ... stcount=50

But I'm sure that if you search there will be other selling addresses.
I can't answer your question why tuningshops in the english speaking region don't pick up on this. Maybe they don't speak german.
All I'm saying is that these pistons wear and that this is a well debated subject on most german BMW forums.
Everyone is free to do with this information as they please. I'm just the messenger.

Rockhopper wrote: ↑Tue Mar 30, 2021 8:47 pm When you are plastigauging the big end shells do you need to stretch the rod bolts to do it so you need a new set each time?

You only need 1 set of bolts. The bolts have to be fittend/stretched 3(!) times, so 1x plastigauge, 1x for fun and 1x for real
The workshop manual has the proper procedure written down (Be sure to get the procedure for your rods; the s54 has been fitted with 2 kinds of rods/rodbolts but I believe the z4m only has the later style bolts (the torx head ones))

GuidoK wrote: ↑Tue Mar 30, 2021 10:28 pm I don't have a current link (don't have an s54 engine ).
I once made a post on Zpost about this topic, and linked to a Facebook topic from some tuner that sold them but apparantly that link doesn't work anymore? (not familiar with facebook policy)
https://www.zpost.com/forums/showpost.p ... stcount=50

But I'm sure that if you search there will be other selling addresses.
I can't answer your question why tuningshops in the english speaking region don't pick up on this. Maybe they don't speak german.
All I'm saying is that these pistons wear and that this is a well debated subject on most german BMW forums.
Everyone is free to do with this information as they please. I'm just the messenger.

So I did some searching around regarding what german workshops say about this matter. Like I said, I don't know why shops in the english speaking part of the world don't pick this up but there are loads of german workshops that refer to this problem:

https://motorschmiede.com/pleuellager-w ... n-service/
"BMW M3 E46
Schon etwas empfindlicher, wir empfehlen bei etwa 120.000 km den Wechsel
Wobei die BMW Z4 E85 und BMW E86 Modelle mit diesen Motoren deutlich früher verschleißen.
BMW Z4 Fahrer empfehlen wir bei etwa 80.000 km zu wechseln. Hier sind oft auch klemmende Ölpumpenkolben der Auslöser."
Here, jammed (or sticking) oil pump pistons are often the trigger. (I think they assume that the wear impedes free/smooth movement from the regulatorpiston, or conterminents get in there...)

https://www.bavariamotors.de/BMW-Pleuel ... sselklappe
"Austausch eines leistungsfähigeren Öldruckregelventils der Ölpumpe " (replacement of a high perforance oilpressureregulatorpiston in the oilpump)

https://www.boschservice-fetzer.de/colibri-967/
"eine Prüfung der Ölpumpe auf Verschleiß" checking the oilpump for wear (as part of their s54 rodbearing service)
They also say: "da mehrere Faktoren wie hohe Drehzahlen, verschlissene Ölpumpen oder auch Kaltstarts den Verschleiß unterschiedlich beeinflussen."
Which means multiple factors like high rpm's, worn oil pumps and coldstarts influence the wear (of the rodbearings)

https://emmenegger-power.ch/store/p1/La ... hseln.html
"Bei den S50/S54 Modellen zudem wird die Ölpumpe geprüft und, wenn nötig, mit einem neuen Druckkolben bestückt "
With the s50/s54, the oilpump will be checked and when necessairy fitted with a new pressurepiston.
(here you can immediately see that labour is expensive in Switzerland )

https://www.h2motors.de/motorrevision-beim-bmw-e46-m3
"Beim S54 sollte in diesem Zusammenhang auch immer die Ölpumpe überprüft werden, die durch den Verschleiß ihres Rädersatzes und im Speziellen des Druckregelkolbens eine mangelhafte Schmierung der Pleuellagerschalen verursachen kann."
With the s54, in this regard, the oilpump should always be checked, which by wear of the cogs, and especially the pressure regulator piston, can cause a deficient lubrication of the rodbearings

https://www.ma-performance.de/m-modelle/e46-m3/
"Die Pleuellagerschalen verschleißen durch die hohen Drehzahlen oder aufgrund eines hängenden Regelkolbens in der Ölpumpe."
The rodbearings wear because of high rpms or because of jamming/wearing regulatorpistons in the oil pump
(not expensive these guys: €1090 inc. VAT for a complete rodbearing service, €80 for the regulator piston and €70 for replacing a leaking pressurevalve)

Here an article from AutoMotorSport about buying 2nd hand e46 M3's, they also hint on that a worn oilpressurepiston may play a role in rodbearingwear:
https://www.auto-motor-und-sport.de/geb ... bleme-smg/

So this is what they think about this issue in germany (apart from what's written on all the forums, they are a wealth of information imho)
In general they say that they think having the piston made out of aluminium is too soft (it's aluminium on aluminium)
I don't know if they wear because of friction or say because of burt oil depost gets trapped in there.
Some pistons show pretty clear gauches/deep scratches. If wear would be very gradual, I would expect more of a shiny wearpatch.
Maybe more than 1 thing is happening here.
I've also seen modified pumps fitted with plastic pistons (bmw OEM parts from other engines).