M engine problems ?
- Thread starter polaxgr
- Start date
markos said:
Thorny Motorsport have an M3 with 180k+ on it and years ago, there was a 230k mile example on US EBay. As said, especially if it's a Z4M it will be 2006+ and so any issues long resolved by then. as long as it's serviced and maintained correctly it will be fine, plenty of 120k+ M3s on Autotrader.
Liverpool
Wonder if that's what caused my engine to go, as it seemed strange at the time that they specified a new VANOS unit along with the engine, when you'd think they'd reuse any part that wasn't part of the problem.RobertRO said:
BTW, mine's was manufactured in Sept 2006 (registered Dec 2006) - and I've done more miles (and rising by about 700 mile a week) on this new engine than I did on the first one
markos said:
My Z4M Coupe is manufactured in Sep. 2006. I've been doing extensive reading on this subject, and I decided to take the hassle of replacing those bolts, instead of assuming the risk. I will do the replacement sometime soon.
Based on what I've read, here are my conclusions:
- the culprit are the bolts #5 in this picture: http://www.realoem.com/bmw/showparts.do?model=DU91&mospid=49422&btnr=11_3004&hg=11&fg=25. If you search the Web you can find a lot of information on the subject. Therefore I will not get into more details;
- any S54 engine installed on Z4 M (Coupe or Roadster) prior to manufacturing year 2007 is subject to the Vanos bolts issue. Although 2007+ cars are very likely to be clear, at this moment nobody seems to be able to guarantee that;
- the problem is not consistent, meaning that some S54 engines can suffer from it, but many others may never experience it. Percentage-wise, it seems that most S54 engines will never show the problem;
- If the bolts break, the engine will definitely be destroyed. Each owner must decide whether he addresses the problem as a preventive maintenance, or lives on with the risk.
For cars out of warranty, please allow me to heavily doubt that.st33ly said:
Look no further than E85/E86 Z4 for several examples of common failures that BMW should have launched a recall for, but instead it just buries the head in the sand:
- sticky electrical power steering, on all Z4 non-M up to manufacturing year 2007;
- broken springs on al Z4;
- ticking noise due to oil starvation of hydraulic lifters, on all Z4 with N52 engines.
Other famous examples:
- HPFP (high pressure fuel pump) failures on all N54 engines (including those on E89 Z4);
- subframe / floor failure on 3 Series E46.
Note: in the United States you may see recalls which for reasons behind my understanding are not applied in Europe, too.
I don't know how much a dealer would charge. I plan on doing the fix myself, in my home garage. It's work on progress, but it moves on sluggish because of my limited time. I hope to come back with a report within a couple of weeks.markos said:
Reading the Zpost article, his car was Dec 2006 manf and the bolts were already the newer type. Could be an explanation for several engines that seemed to suddenly go kaput mmmfives being a case in point.
Is this a problem likely to happen early on in the engine's life? Haven't heard of any Z4Ms blowing up for a while. Something else to worry about
Is this a problem likely to happen early on in the engine's life? Haven't heard of any Z4Ms blowing up for a while. Something else to worry about
I have replaced those "Vanos bolts" (actually the bolts are fixing the valve train gears onto the camshafts).
There's plenty of information on the Web on this subject, therefore I will not duplicate it. I will only mention my own conclusions.
1. My car (Sep. 2006 Z4 M Coupe) had the old version of the bolts, hex socket - instead of the newer torx socket bolts. This confirms the theory that any S54 build before end of 2006 may have the issue.
2. Although they were the "old" model, all those bolts (6 on the intake, 6 on the exhaust camshafts) were tight and absolutely all right. Car mileage: about 45,000 Km. In other words, the engine was fine and there was no risk on the medium-term future. However, there was no guarantee that these bolts would have made it fine throughout the lifetime of the engine. Since I was there, I replaced them with the newer model, using blue Loctite to secure them. Important: the newer model is the same size and the same strength ( 8.8 ) as the old model. The only difference is the head, torx versus hex. So you can fit old model bolts with blue Loctite, it's the same as using the new model.
Conclusion: don't do the preventive replacement of these "Vanos bolts" unless there are signs of issues (e.g. unexplained noises in the Vanos area, or failing the test ref. #4 below).
3. DO NOT attempt to replace these bolts by your own, unless you have all the necessary BMW special tools. I insist on this. If you have all the tools are you're mechanically inclined, then it's a great experience doing it. If not, take it to the dealer, or you will most likely mess the timing. Ask me how I know...
4. Simple test. Once the valve cover is out (for example, with the occasion of a valve lash check every 30,000 Km), you can run a simple test to check if the bolts are all right. Grab strong on the intake camshaft sproket (ideally below the chain) and try to wiggle it backwards and forward on the axial direction of the camshaft. See the last picture below. There should be absolutely no play at all. Make sure you don't mistake the chain play onto its sprocket, for sprocket play onto the camshaft. Repeat the same procedure for the exhaust camshaft.
Then, for 3 times, do the following loop:
- rotate the engine by 180 degrees (1/2 turn);
- repeat the test for both camshafts.
If no play is noticed what-so-ever, and in addition there are no strange noises in the Vanos area when the engine is running, then your Vanos bolts are very likely to be all right.
Pictures:
There's plenty of information on the Web on this subject, therefore I will not duplicate it. I will only mention my own conclusions.
1. My car (Sep. 2006 Z4 M Coupe) had the old version of the bolts, hex socket - instead of the newer torx socket bolts. This confirms the theory that any S54 build before end of 2006 may have the issue.
2. Although they were the "old" model, all those bolts (6 on the intake, 6 on the exhaust camshafts) were tight and absolutely all right. Car mileage: about 45,000 Km. In other words, the engine was fine and there was no risk on the medium-term future. However, there was no guarantee that these bolts would have made it fine throughout the lifetime of the engine. Since I was there, I replaced them with the newer model, using blue Loctite to secure them. Important: the newer model is the same size and the same strength ( 8.8 ) as the old model. The only difference is the head, torx versus hex. So you can fit old model bolts with blue Loctite, it's the same as using the new model.
Conclusion: don't do the preventive replacement of these "Vanos bolts" unless there are signs of issues (e.g. unexplained noises in the Vanos area, or failing the test ref. #4 below).
3. DO NOT attempt to replace these bolts by your own, unless you have all the necessary BMW special tools. I insist on this. If you have all the tools are you're mechanically inclined, then it's a great experience doing it. If not, take it to the dealer, or you will most likely mess the timing. Ask me how I know...
4. Simple test. Once the valve cover is out (for example, with the occasion of a valve lash check every 30,000 Km), you can run a simple test to check if the bolts are all right. Grab strong on the intake camshaft sproket (ideally below the chain) and try to wiggle it backwards and forward on the axial direction of the camshaft. See the last picture below. There should be absolutely no play at all. Make sure you don't mistake the chain play onto its sprocket, for sprocket play onto the camshaft. Repeat the same procedure for the exhaust camshaft.
Then, for 3 times, do the following loop:
- rotate the engine by 180 degrees (1/2 turn);
- repeat the test for both camshafts.
If no play is noticed what-so-ever, and in addition there are no strange noises in the Vanos area when the engine is running, then your Vanos bolts are very likely to be all right.
Pictures: