Vanos Gears?

[clarkh]

I knew this was going to happen!!

All sounds a bit rough at idle so took the car to the local dealer to get a mechanic to have a listen. Got the most experienced 'M' mechanic out and he recons it's the Vanos gears? but not the hydraulic main VANOS bit?!?. Apparently it'll be fine to drive and many people just continue to drive them with the fault and the sound.

They've said that there are two sets of something that needs to be purchased at around £400 each and it'/s take around 7 hours to fit, BMW quote a fixed price for this so thankfully it won't be 7 x £117.50 for their hourly charge.

Does anyone know what there talking about?

Thanks

[c_w]

I think this is THE common vanos noise we hear on the S50s, from what I've read most of them make some kind of noise to some degree but the VANOS itself works ok. Mine has a newish looking VANOS unit on it, this is quiet, but the gears have a slight rattle when hot as the tinyest of slack would produce this noise but perform normally otherwise.

The VANOS is effectively 2 parts; two sets of gears which are on the end of the camshafts (the gears slide inside each other to alter cam timing), and 2 solenoids on the end which turn the gears (the silver bit on the end of the engine which is hydraulically operated with engine oil).

[clarkh]

Thanks, that makes sense, the mechanic said that I'm probably only noticing more now because of the hot weather and the oil is thinner. The vanos was changed 19,000 miles ago and it's recently been tested with no faults.

He said that I'm fine to drive it, so I guess I'll save a bit of cash up and have it done when I can afford it.

Thanks for explaining that to me, I just hope by driving it I don't cause and major and permanent damage!

[c_w]

I think that this noise isn't terminal and I reckon that most of these engines have this noise to some degree. The noise is from the pairs of meshing gears, a very tiny amount of play so the vanos operation should be ok as its operated by the vanos solenoids on the end (this is the main part to worry about IMO).

I think you're right in saying when the oil is hotter/thinner its more noticeable. Mine currently has Mobil 1 0/40 in, it used to have Castrol 10/60 (which is thicker) in it but can't remmeber if it was quieter then or not.

[ZZZEMMCO]

The Gears can be taken off and can be repositioned on the spline , this can cure the wear noise in many cases.Specialists do it--Dealers do the renew gear fix for easy £££££££.

[c_w]

The Gears can be taken off and can be repositioned on the spline , this can cure the wear noise in many cases.Specialists do it--Dealers do the renew gear fix for easy £££££££.

That's interesting, never heard of that. Who do you know who does this?

[M3 Compact]

It isn't just the S50s. :shock:

My S50 Vanos is quiet (I use 10W 60 oil due to high temps), the vanos noise is something I've been aware of having had previous S50 noisy Vanos experiences. (The oil may possibly help, I haven't used it with 0W 40 for a comparison.)

I have a 530i that makes a 'dampened' noise, not dis-similar to S50 Vanos noise. :shock: It's been to the dealer twice, the second time for a Master Tech to listen and I've been assured that it's 'normal' for these engines. :shock: (Reported as Vanos gear rumble, I was assured that none have actually failed.)

Taking it upon myself to investigate further, I've listened to a number of M54 engines and many have made this noise. (Very similar to S50 Vanos rattle, but dampened/muted.) It generally occurs at around 2K revs when commencing 'overrun'.

It transpires that the M54 engines use 'rubberised' gears to suppress noise, to me this smacks of inherent noise that is being hidden.

Does a noisy S50 Vanos unit ever actually fail due to the gears? :?: (They fail with the chocolate bolts and solenoids seizing, but I've never heard of actual gear failure.)

Providing the actual gears don't fail, I can't see any way in which the Vanos malfunctioning could cause further/referred engine damage, whatever position the Vanos unit sticks in, has to be within the parameters of operation, therefore can't cause a valve crash.

The Gears can be taken off and can be repositioned on the spline , this can cure the wear noise in many cases.Specialists do it--Dealers do the renew gear fix for easy £££££££.

That's interesting, never heard of that. Who do you know who does this?

Agreed, very interesting, never heard that before. 8)

[chippy]

My S50 coupe is still on its original vanos at 57000 miles and has had a slight 'grumble' coming down from 2000rpm for ages.

A very good friend of mine who is a head service manager for a bmw dealership said there is no point throwing money away on replacing it as long as the vanos unit is operating ok.

[danp]

My M3 Evo is a bit growly on the VANOS front, and idling / low revs can be a bit lumpy + hesitant. The supplying BMW dealer (from new) said VANOS needed doing (and the tech wanted to do it on the side...) but my local dealer said not to bother, he'd heard a lot worse...

M3_compact - what do you mean by chocolate bolts ?! The original, weaker, non-recall bolts ?!

One theory is that the increased vibration from worn VANOS gears not meshing together brilliantly could *possibly* cause a VANOS bolt to snap, thus causing the solenoids to push out the front of the engine and a big oil leak, a friend basically had this happen, but you can put things back together without new parts.

I've got 8 x new VANOS bolts plus the VANOS filter from BMW (abt a tenner) so will prob get them put on this week and see if that makes any diff (have read that changing the filter might help). Plus may then change the oil to a semi-syn 10/40, and see if that makes a diff.

PS Total BMW has a section on the S50 engine in the current issue, worth a read, quite interesting - also mentioned a company that re-furbs / fixes VANOS as opposed to the £1299 replacement cost, might give them a call.

PPS Also said that they are going to produce a guide to "fixing" the VANOS problems in a future issue ! (soon-ish)

PPPS U prob know but BMW can test if ur VANOS if working OK, abt 30mins labour, note that they are not replacing VANOS under EW these days if it's just noisy...needs to have a fault.

[Col]

Mine is on it's original Vanos it's now done 67,000, (had the longer bolts under recall).

It like nearly all other S50's makes the notorious grumble sound when coming down from about 2k revs.

I too have been told not to bother paying for new set of gears, the noise will return.

I'd be interested to know how many actual engine failures have been caused by the the vanos breaking down. from what I understand there isn't as many weare led to believe:?:

[spunkym]

Ah, VANOS. You can get a good idea of how it works by reading this thread over on the Z3 roadster forum... http://www.zroadster.net/forum/viewtopic.php?t=8960&highlight=

[gerry]

Does anybody know the part number for the bolts?

[Col]

Does anybody know the part number for the bolts?

Open this link or copy it into your browser

http://www.realoem.com/bmw/showparts.do?model=CM92&mospid=48075&btnr=11_1575&hg=11&fg=15

[pies]

My newly acquired MC (99 S, 41k, Estoril) also has a bit of a lumpy idle and a distinct whine through the rev range. :?

My girlfriend described it as being 'like taking off in an aeroplane'...by which i think she means the whine is like a turbine (or maybe its just the acceleration :twisted: ).

Now from memory i think the other cars i test drove had the same sort of sound. I'm not sure from reading other people's descriptions if this is the infamous 'vanos noise' or just a characteristic of the engine....

perhaps i'm just a bit sensitive as its my first week of ownership, i've got no warranty and i'm expecting the worst at any moment :shock:

Anyway, the car's in for a check at Munich Legends on saturday, so fingers crossed!

[c_w]

I don't think a whine is a common characteristic of the engine; the rattly VANOS gears usually are inaudible from within the car with the windows up.

The only whine I could think of is transmission whine, either gearbox, or more commonly, a bit of diff whine.

[M3 Compact]

My newly acquired MC (99 S, 41k, Estoril) also has a bit of a lumpy idle and a distinct whine through the rev range. :?

My girlfriend described it as being 'like taking off in an aeroplane'...by which i think she means the whine is like a turbine (or maybe its just the acceleration :twisted: ).

Now from memory i think the other cars i test drove had the same sort of sound. I'm not sure from reading other people's descriptions if this is the infamous 'vanos noise' or just a characteristic of the engine....

perhaps i'm just a bit sensitive as its my first week of ownership, i've got no warranty and i'm expecting the worst at any moment :shock:

Anyway, the car's in for a check at Munich Legends on saturday, so fingers crossed!

Viscous coupling on the fan? :?:

[AJL]

For the record i had noisy vanos gears, i have just had these repaced under EW and now no noise at all :D

[pies]

Well the 'whine' must be standard issue because the car went in for a very thorough check at Munich Legends on Saturday, and they reported back that the car has no mechanical faults :D

Phew! After reading all these postings about VANOS bolts/gears etc. its a big relief to find you've bought one that's running ok.

Found ML very helpful and knowledgable about the MC and i'm going to send it back there to have a couple of minor things done.

[cragg711220]

Hey pies, how much was your check at Munich Legends? As a new owner I would be keen on having the same check done on mine.