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Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 4:17 am
by BMWZ4MC
Hi John, as Lower has said there have been occasional reports of the F20C spinning a bearing, but it’s rare. There was a period when S2000s were very cheap cars and I suspect a few were neglected for periods of their life. Since most consume oil, it’s actually surprising that more haven’t had problems.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 9:13 am
by Gwest44
As has already been said this makes for s**t reading and I feel for the OP’s that have been effected - in addition I’m now shitting myself thinking that mine might go at anytime now I’m about to reach 100k.

Excuse my ignorance and inabity to extract the relevant detail but if I take the car to my independent what should I be asking him to do to reduce the probability of this happening on mine - he did my inspection II 2,000 miles ago but would appear this is irrelevant as a deterrent to the issue?

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 9:31 am
by mr wilks
Gwest44 wrote: Thu Mar 14, 2019 9:13 am As has already been said this makes for s**t reading and I feel for the OP’s that have been effected - in addition I’m now shitting myself thinking that mine might go at anytime now I’m about to reach 100k.

Excuse my ignorance and inabity to extract the relevant detail but if I take the car to my independent what should I be asking him to do to reduce the probability of this happening on mine - he did my inspection II 2,000 miles ago but would appear this is irrelevant as a deterrent to the issue?
Put simply the only way for peace of mind is have the bearing shells replaced as a matter of routine maintenance , circa £1k job , opening the bottom end up just to check them then putting the originals back is not really viable :(

Thread here might be worth a read viewtopic.php?f=9&t=95781 :thumbsup:

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 9:49 am
by tomscott
Its not the smallest job so makes sence to have other jobs done at the same time.

Mounts, bolts etc

I wouldn't be panicking this happens on a rare basis and there are so many different factors that its impossible to give an indication on what each cars wear it like unless you have owned the car since new.

Ive been here for 8 years and have seen there has been around 6-7 instances, its a forum people come here for these types of problems so its not common. On the other hand these cars are hitting bigger milage now.

Just add it to the next round of maintenance.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 10:14 am
by Jembo
I’d also check how often they’d done it before - every so often or known for undertaking it regularly without neg feedback.

I’m also not clear whether there are now recommended upgraded shells / bolts that are available (the ones lined with tin mentioned in video instead of copper) or whether stick to OEM

Cheers

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 10:50 am
by exdos
In view of the fact that the bearings shells of most S54 engines, of which there are 12 parts per engine, will show signs of pitting/scoring after the engine has done significant mileage, the fact remains that only a very small number of bearings actually fail catastrophically (i.e. only 2 bearing shells per failed engine), would suggest to me, at least, that this is not, itself, the fundamental cause of bearing shell failure/destruction.

OTOH, how would the failure of the connecting rod bolts, by stretching beyond tolerance, manifest itself other than by permitting the crankshaft to hammer the bearing shells into much thinner pieces?

IMO, if you're going to inspect the bearing shells, then you should also commit to changing them AND the con-rod bolts for new upgraded parts.

A bad gear shift, say, into 2nd gear instead of 4th, would also be an occasion which could cause catastrophic bearing shell failure.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 10:52 am
by ph001
tomscott wrote: Thu Mar 14, 2019 9:49 am Ive been here for 8 years and have seen there has been around 6-7 instances, its a forum people come here for these types of problems so its not common. On the other hand these cars are hitting bigger milage now.
Quite true, also a good indicator is how many instances there are of it over on M3Cutters. There are 1000+ S54 M owners on there and reports of failures are under 1%.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 2:28 pm
by R60BBA
tomscott wrote: Thu Mar 14, 2019 9:49 am Its not the smallest job so makes sence to have other jobs done at the same time.

Mounts, bolts etc

I wouldn't be panicking this happens on a rare basis and there are so many different factors that its impossible to give an indication on what each cars wear it like unless you have owned the car since new.

Ive been here for 8 years and have seen there has been around 6-7 instances, its a forum people come here for these types of problems so its not common. On the other hand these cars are hitting bigger milage now.

Just add it to the next round of maintenance.
It’s not rare, in fact it’s becoming more common.

Unless you have owned the car from new, it’s impossible to know how it has been looked after by former keepers.

£1,000 to get this sorted isn’t a big deal and should be done on any car over 70,000 miles. If you cannot afford this then you should not be driving one of these.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 2:59 pm
by tomscott
It depends who you talk to as I said forums are places people bring these issues to light and obviously the Z4 is lower volume than the M3 but its certainly not common.

Same with Porsche I always thought it was internet scaremongering until I bought a car and 2 weeks later had a 12k bill for a rebuild...

That being said you still have to be very unlucky.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 3:16 pm
by R60BBA
tomscott wrote: Thu Mar 14, 2019 2:59 pm It depends who you talk to as I said forums are places people bring these issues to light and obviously the Z4 is lower volume than the M3 but its certainly not common.

Same with Porsche I always thought it was internet scaremongering until I bought a car and 2 weeks later had a 12k bill for a rebuild...

That being said you still have to be very unlucky.
There’s a lot less Z4Ms than M3s and I’d even stipulate that as a 2 seater, they are more likely to have less miles on em than M3’s.

They are also up to 2 years younger than the last E46 M3s and 7 years younger than the first MK20s.

However they have the same engine and so the same thing can occur as per the unfortunate 2 examples in this very thread.

In my post I wasn’t just referring to examples on forums where people have posted about their rod bearing failures, but I was also taking into account discussions which I have had with various M specialist garages on this, who have all confirmed that it is becoming more common in recent years.

You also cannot ignore that MK20 M3s had this job done under recall, which affected thousands of cars...further reinforcing it has been a problem area from day 1.

I did mine for peace of mind. The shells came out clean and I could’ve waited another 30,000 miles or so however I could’ve been ‘unlucky’ as you put it and spun a bearing in 5,000 miles.

Either way I no longer have that worry as the job is done. Now my concern is the flippin’ boot floor. :roll:

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 3:53 pm
by Bing
I better put mine up for sale because apparently I shouldn't be driving it, given it's on 83k, has not had the shells replaced and I don't have a spare grand right now ... I must also remember to knock £1k off the asking price because the shells have not been done, and I am sure that will become a common bargaining point in the near future :P

In all seriousness, based on everything everyone is saying, if you can afford to have this done by 70k (an arbitrary number by the way, with no empirical evidence presented or probably even possible to present) then you probably should. If you can't then budget to do it at about 80-100k and in the meantime pay attention to the car - regular interim oil & filter changes, on-time servicing, visual inspection, regular oil analysis, and treat the car with mechanical sympathy.

EDIT - sorry, I probably should have put a smiley face in here somewhere... Now corrected for tongue-in-cheek :lol:

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 4:46 pm
by mmm-five
I think they should be done every Insp.II :P

That’s about 50-55,000 miles for daily drivers, or 40,000 miles for garage queens/weekend cars...and work out about £500 extra per year for daily drivers or £100/year for the rest.

Or about £50/year in my case (if you don’t include the cost of my replacement engine) :?


Whichever way you look at it, it’ll cost less than VED :thumbsup:

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 4:54 pm
by Bing
Ha, that's not necessarily a s**t idea. Funnily enough 100k will be around my second Insp 2. And as I have already said, that's what I'm budgeting towards.

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 5:07 pm
by R60BBA
mmm-five wrote: Thu Mar 14, 2019 4:46 pm I think they should be done every Insp.II :P

That’s about 50-55,000 miles for daily drivers, or 40,000 miles for garage queens/weekend cars...and work out about £500 extra per year for daily drivers or £100/year for the rest.

Or about £50/year in my case (if you don’t include the cost of my replacement engine) :?


Whichever way you look at it, it’ll cost less than VED :thumbsup:
Well put 8)

Rod bearing failure - what to do?

Posted: Thu Mar 14, 2019 5:28 pm
by mmm-five
Once I’ve put my ‘new’ engine in (47k on it), the only original parts will be cats, bonnet, roof & gearbox.

If I’d done the rod bearings earlier, I would have still had a 140,000 mile old engine, but with new bearings...so you just know I’d be needing vanos, cams, rods, etc. shortly too.

This way I’ve now got a low mileage car again :P