///M S54 valve gear excessive wear
///M S54 valve gear excessive wear
As above, a 56 plate BMW Z4 in my close acquaintance has an S54 ///M 3.2 litre unmodified engine and had a pair of camshafts fail by excessive lobe wear 18,000 miles ago. Now one of the replacements has started to fail too. The car is serviced more frequently than the specified intervals, uses the correct grade of oil, has its fluids checked assiduously, but still this happens. It is used on trackdays but is more a road vehicle than a track car. The workshop that services it, a very well respected independent, has no clear explanation so, over to the zroadster massive.
Re: ///M S54 valve gear excessive wear
Only a humble guess from me - but my thoughts go immediately to upper engine oil starvation due to either low oil pressure, thick oil and short journeys or some other mechanical problem e.g. oil pump Very interested to see the range of views on this one.
Re: ///M S54 valve gear excessive wear
One of the thoughts from the BMW indie was that fast cornering on the trackdays might lead to momentary oil starvation but that he thought the much more stressed big ends would fail first and these were checked when it happened the first time as a precaution. On that first occasion the car was en route to Nice and the noise became louder as the trip went on. This time it seemed to happen fairly quickly over a short period. It is almost never used for short journeys and the oil is changed at 2/3 of the specified intervals. An up-rated oil pump is being considered though. Dry sumping would be best, but probably prohibitively expensive to do. Thanks for the thought though.Del wrote:Only a humble guess from me - but my thoughts go immediately to upper engine oil starvation due to either low oil pressure, thick oil and short journeys or some other mechanical problem e.g. oil pump Very interested to see the range of views on this one.
See here, the first time's damage:
Re: ///M S54 valve gear excessive wear
did it have the running in service done as they use a different grade oil which may block oil ways. also has it been serviced regularly early in its life time. ?
Z3 2.8 Progress Journal (Mine)
Z3 1.9 Sport Progress Journal (Wifey's)
I have an element of 'M-styling' on my car, If that's a good enough reason for the manufacturers to adorn a 320 with the M badge, then its certainly a good enough reason for me..
Re: ///M S54 valve gear excessive wear
I'm aware that some very early S54 engines (pre-Z4M) had issues with a bad batch of bottom end bearings and that various Vanos issues have been alleged. I have never heard of any general problem surrounding either oil circulation or the camshafts. Bit of a brain teaser this one.
Re: ///M S54 valve gear excessive wear
The initial S54 recal also included replacement of the oil pump due to "unfavourable tolerances in the oil pump".
That damage really looks like oil starvation. Do you know if the followers were also replaced last to the cams were changed?
That damage really looks like oil starvation. Do you know if the followers were also replaced last to the cams were changed?
2001 M roadster S54 Laguna Seca Blue
Re: ///M S54 valve gear excessive wear
Are all the lobes the same ?
Gazza
"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"
Z3 S54 M roadster , BMW Z1, BMW M3 CSL, Z4M Coupe
"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"
Z3 S54 M roadster , BMW Z1, BMW M3 CSL, Z4M Coupe
Re: ///M S54 valve gear excessive wear
Yes it did have its very important running in service (supplying dealer) with the first and only previous owner, and was serviced more than regularly (the service indicator has been set to 66% of the service interval to render the services more frequent). It has been owned since 2009 and always serviced using approved 'Longlife' oil, normally Mobil 1 I believe.gookah wrote:did it have the running in service done as they use a different grade oil which may block oil ways. also has it been serviced regularly early in its life time. ?
Re: ///M S54 valve gear excessive wear
You're right about spinning bottom-end shells on some earlier engines and Vanos problems too, but this is a later model past these problems.Del wrote:I'm aware that some very early S54 engines (pre-Z4M) had issues with a bad batch of bottom end bearings and that various Vanos issues have been alleged. I have never heard of any general problem surrounding either oil circulation or the camshafts. Bit of a brain teaser this one.
Re: ///M S54 valve gear excessive wear
Yes all followers and both camshafts were replaced. There was a question about the quality of the oil because a mechanic in Nice (where the first instance occurred) looked at the car and pronounced the oil "sheeet" . However it was all traced back and the oil was genuine and correct grade, so that was a herring rouge.siwilson wrote:The initial S54 recal also included replacement of the oil pump due to "unfavourable tolerances in the oil pump".
That damage really looks like oil starvation. Do you know if the followers were also replaced last to the cams were changed?
I have a Ford Pinto engine in my Westfield and that is notorious for having a blocked cam spray bar which gooses the camshaft, but in this engine the oil doesn't rely on a spray bar.
Re: ///M S54 valve gear excessive wear
This time it seems on initial looking that it's exhaust side number five or six, I'm told. Last time it was more than one lobe but by no means all. I have the old camshafts but they have been hanging around the garage for a fair time and really need degreasing to examine properly.Gazza wrote:Are all the lobes the same ?
Thanks to all who have responded, it really is a brain teaser and at this rate an expensive one too.
Re: ///M S54 valve gear excessive wear
My thoughts are that the camshaft wasn't 'run up' properly after installation, the camshaft has a special lube applied to the lobes and then run through a sequence of revs for approximately 20 minutes. Also new camshaft bearings should be fitted and the oilways aligned.
I would suggest a visit to an engine builder for his advice as to why this happened.
I would suggest a visit to an engine builder for his advice as to why this happened.
Gazza
"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"
Z3 S54 M roadster , BMW Z1, BMW M3 CSL, Z4M Coupe
"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"
Z3 S54 M roadster , BMW Z1, BMW M3 CSL, Z4M Coupe
Re: ///M S54 valve gear excessive wear
I'll suggest asking the indie what procedure is specified on installation and see what he says. Again, thanks for the input chaps.