S54 rod bearing

[AndyBeech]

Im glad people are fairly talking sense instead of arguing over an item that is most certainly an issue. The simple fact is £1500 is cheaper than a whole engine rebuild and if you get to 80-100k its worth the time and money to sort for piece of mind if the car is a long termer.

I think it's called a debate, I don't recall anyone arguing? At the end of the day it's easy to say drop £1500 or so and give advice to that affect when it's not you that has to spend that money, even if it does pale in significance to a full engine rebuild. If I'm dropping that kind of money into something I want balanced opinion from both sides of the fence with facts and examples to back it up, which as the thread has gone on has been well provided from some clearly knowledgeable people (and knowledge already out there). The start of the thread didn't provide many facts or examples for me (apart from the OP obvs), just speculation and opinion, which is fine, it's an internet forum after all. But at the end of the day it is just that, an opinion on what could be deemed a sensitive subject. (Anyone selling an M car on here that has 80k plus on it will now come under scrutiny regarding rod bearing's for example and now have a tougher car to sell...? Maybe that's reflected in prices already, I don't know tbh) I only mention that as a guy at the beginning of the thread posted that he was now worried about buying an M, which I think is a massive shame as the issue wasn't put into context at the time. Not to say that the same guy shouldn't also go into M ownership with eyes open, just the context wasn't there.

As mentioned before throughout this thread, there's plenty of S54's that have no doubt gone well into the 100k's with no issues and those with low mileage who have had issues. As someone said earlier there doesn't seem to be much pattern with who will suffer a failure and who won't, it's a bit luck of the draw from what I can tell so far although the higher the mileage pushes through the 100k barrier the more potential there is for wear certainly seems apparent.
I think everyone on this thread has been talking sense so far, if a debate has lead to a more detailed thread on the issue then I can only see that as a good thing personally

 

[exdos]

As mentioned before throughout this thread, there's plenty of S54's that have no doubt gone well into the 100k's with no issues and those with low mileage who have had issues. As someone said earlier there doesn't seem to be much pattern with who will suffer a failure and who won't, it's a bit luck of the draw from what I can tell so far although the higher the mileage pushes through the 100k barrier the more potential there is for wear certainly seems apparent.

Funnily enough, with the earliest S54 engines in the "Engine of Damocles" era, most of the BS failures occurred with relatively low mileages, as if once an engine had survived a certain mileage it was less likely to suffer a catastrophic engine failure thereafter.

 

[AndyBeech]

As mentioned before throughout this thread, there's plenty of S54's that have no doubt gone well into the 100k's with no issues and those with low mileage who have had issues. As someone said earlier there doesn't seem to be much pattern with who will suffer a failure and who won't, it's a bit luck of the draw from what I can tell so far although the higher the mileage pushes through the 100k barrier the more potential there is for wear certainly seems apparent.

Funnily enough, with the earliest S54 engines in the "Engine of Damocles" era, most of the BS failures occurred with relatively low mileages, as if once an engine had survived a certain mileage it was less likely to suffer a catastrophic engine failure thereafter.

Absolutely, bizarre really! Going back to the rev limiter on your Z3 being different, could we take it that if we don't rev the car to it's 8000rpm limit and more like 7400rpm will we massively prolong BS life? I guess that does defeat the object of the engine somewhat, saving the 8000rpm blitz's to a minimum? (Track day's excused obviously!)

 

[tomscott]

Thing is this is not the first thread there are many, many threads which most get quite heated yet all come to the same conclusion hence my opinion. I sold my car, but if I had kept it, I wouldn't have thought twice. If I were buying another I would buy with this in mind.

Not necessarily anyone being flamed for selling a higher milage car. It about letting people know that are looking to buy, a now common higher milage car, that its worth bearing in mind.

No pun intended.

 

[Lower]

As mentioned before throughout this thread, there's plenty of S54's that have no doubt gone well into the 100k's with no issues and those with low mileage who have had issues. As someone said earlier there doesn't seem to be much pattern with who will suffer a failure and who won't, it's a bit luck of the draw from what I can tell so far although the higher the mileage pushes through the 100k barrier the more potential there is for wear certainly seems apparent.

Funnily enough, with the earliest S54 engines in the "Engine of Damocles" era, most of the BS failures occurred with relatively low mileages, as if once an engine had survived a certain mileage it was less likely to suffer a catastrophic engine failure thereafter.

Absolutely, bizarre really! Going back to the rev limiter on your Z3 being different, could we take it that if we don't rev the car to it's 8000rpm limit and more like 7400rpm will we massively prolong BS life? I guess that does defeat the object of the engine somewhat, saving the 8000rpm blitz's to a minimum? (Track day's excused obviously!)

My understanding of bearing cavitation is that it occurs at high rpms. Therefore would make sense that if you lower the redline you reduce the likelihood of cavitation.

 

[Argenta]

Ok so the general direction is to check my 166000km engine, even if it runs perfectly fine without rattles etc?

Another angle on oil; is there any idea running on 5w-50 Mobil1 etc..? A bit easier on the engine cold, but also good warm. (Ran it for years in my old car (1998cc, 340hp 5-cyl), good pressure even on trackdays etc)

 

[mr wilks]

Ok so the general direction is to check my 166000km engine, even if it runs perfectly fine without rattles etc?

Another angle on oil; is there any idea running on 5w-50 Mobil1 etc..? A bit easier on the engine cold, but also good warm. (Ran it for years in my old car (1998cc, 340hp 5-cyl), good pressure even on trackdays etc)

Not on Mobil but have switched to Millers CFS 10 60
Used their products for many years & you can only find praise in any reviews
Less friction so less heat so hopefully less wear :? & also cold start qualities prompted my switch
http://www.millersoils.co.uk/automotive/tds-automotive.asp?prodsegmentID=924&sector=Motorsport

 

[PerryGunn]

Posted on behalf of a certain Mr. Slone as he can't post pictures from his iPad...

 

[srhutch]

As mentioned before throughout this thread, there's plenty of S54's that have no doubt gone well into the 100k's with no issues and those with low mileage who have had issues. As someone said earlier there doesn't seem to be much pattern with who will suffer a failure and who won't, it's a bit luck of the draw from what I can tell so far although the higher the mileage pushes through the 100k barrier the more potential there is for wear certainly seems apparent.

Funnily enough, with the earliest S54 engines in the "Engine of Damocles" era, most of the BS failures occurred with relatively low mileages, as if once an engine had survived a certain mileage it was less likely to suffer a catastrophic engine failure thereafter.

Bit like the nikasil 2.8 engines IIRC.

 

[Darren Slone]

Posted on behalf of a certain Mr. Slone as he can't post pictures from his iPad...

thanks Perry! :lol:

 

[original guvnor]

 

[mr wilks]

Yeah i like that

 

[pHilli0]

After all the drama of my cams being ruined I am really worried about my rod bearing shells. The engine sounds fine after the top end was rebuilt but after so much cash I would not be laughing if the shells gave up.
The car is at 93k now. How reliable is the oil sample test ??? Anyone know what the cost is ?

 

[Z4M-2006]

Wouldn't it just be prudent to just have them done at 90k + miles Phil ?

If the shells are removed, they are gonna be worn at that mileage...that goes without saying..

 

[pHilli0]

Wouldn't it just be prudent to just have them done at 90k + miles Phil ?

If the shells are removed, they are gonna be worn at that mileage...that goes without saying..

Oh It is definitely a good idea. It's on the top of my to do list regardless of being 1500 or what ever. I was just interested what the oil sample actually shows. As people were implying that you can determine the condition from the results which doesn't make much sense to me?. If it is a cheap thing to get done I might if it genuinely useful.

 

[exdos]

The samples look for high lead and copper readings in oil which has been in use for around 7,500miles. Normal copper = 8ppm and normal lead = 5ppm. There are umpteen threads on this subject on various BMW forums (particularly US-based) where some samples show readings of > 40ppm for copper and > 20ppm for lead but without showing catastrophic bearing shell failure. Likewise, low and average copper and lead readings indicate low bearing shell wear but are no guarantee that catastrophic failure will not occur.

The apparent lack of correlation between bearing shell wear and bearing shell failure leads me to think that a catastrophic failure is caused by a sudden event of fatigue of a con-rod bolt, which would instantly make the space inside the conrod and around the crankshaft eccentric, which would then suddenly cause a delay in the movement of the con rod/piston when the crankshaft rotates, thus creating the banging noise heard when failure occurs.

Whilst the S54 engine often seems to show excessive bearing shell wear, I think when catastrophic failure does occur the real culprit is more likely to be the con rod bolts and oil analysis wouldn't be able to predict this occurrence.

 

[Beedub]

the oil will show signs of lead BUT..... yo need to be doing it over a long period of engine life, as this will show the levels of lead/copper increasing etc giving you a decent indication of what this needs to be done, considering your recent expenditure you'd be MAD to not get this done asap at that mileage, if this was a 50k car id probably think little differently.

hopefully you crack the engine and all is perfect!

 

[Z4M-2006]

I dare say that phils car may show some kind of higher reading anyway.... residual contaminants from the cam and follower failure may still be in the sump,regardless of an oil change..

 

[pHilli0]

the oil will show signs of lead BUT..... yo need to be doing it over a long period of engine life, as this will show the levels of lead/copper increasing etc giving you a decent indication of what this needs to be done, considering your recent expenditure you'd be MAD to not get this done asap at that mileage, if this was a 50k car id probably think little differently.

hopefully you crack the engine and all is perfect!

Wise words ..

 

[pHilli0]

I dare say that phils car may show some kind of higher reading anyway.... residual contaminants from the cam and follower failure may still be in the sump,regardless of an oil change..

Hmm yea makes sense. I didn't really know oil analysis was a thing before I read about it in this forum.