Let me point out that 1998 was the first production year for european E39 M5s. Most quirks were fixed in 2000 when the E39 M5 was launched in the US.
What does Vanos do? ****************************
The Vanos units change the timing reationship between crankshaft and the four separate camshafts. This directly controls valve timing both on intake and exhaust. This is what gives the wonderful flat torque curve. This is what gives the wonderful full-load-high-RPM engine note. This is what makes an S62 engine an S62.
Two kinds of Vanos noise in the E39 M5 ****************
There are two kinds of Vanos noise.
The first kind is loud rattle only heard at startup and stops within a minute. This is fixed by installing the Vanos oil pressure accumulator.
The second kind is loud rattle (like an old Mercedes diesel) that gets worse the warmer the engine is. This calls for replacing parts of the Vanos units.
History of extended warranty *****************
There has been several fixes on the Vanos system. In the US, BMW initially denied any problems, but later after pressure from owners (many of whom are members of this board) issued free Vanos oil pressure accumulator coverage until December 2003 / 3 years / 100000 km .
History of fixes **********************
First of all, on cars built up to November 2000, get the Vanos oil pressure accumulator installed. This is a compressed gas oil pressure vessel and a shutoff valve that takes high pressure oil (200 Bar) from both Vanos hydraulic pumps while the engine is running and stores it until the nest enigine start. There is an electromagnetic shutoff valve that keeps the pressurized oil in the vessel when the engine is stopped.
(very neat design, much better than the electrical priming pump they used before)
The installation procedure (takes about 1 day for 1 mechanic) is described in Service Bulletin 11 01 01 (661) issued March 2001.
This warranty action expires December 2003 / 3 years / 100000 km, whichever happens first, so hurry up.
This should take care of all Vanos noises that disappear by themselves a few seconds after starting the engine.
Most Vanos units will still make a bit of noise. If the diesel-sounding Vanos noise (after warm-up) is more than you are willing to accept, or if it keeps getting worse the more miles you put on the meter, you need to get some parts inside the Vanos units replaced. To get this under warranty, you need to be kind to your SA.
(btw there is no such thing as a completely noiseless Vanos, but in the case of my car subjectively 75% of the noise disappeared)
The production-dates and engine-numbers below are from BMW Germany recomending replacment of certain Vanos parts on S62 engines in case of loud rattles.
On M5 built before mid-July 2000 (engine number 60232305): replace
spline-shaft (BMW part number 11 36 4 781 417, 4 needed per engine) and
spring discs with support washers (BMW part number 11 36 7 833 218, 4 needed per engine).
Built after that, but before mid-September 2001 (engine number 60572609): replace just the spring discs with support washers (BMW part number 11 36 7 833 218, 4 needed per engine).
Built after that: everything ok from the factory.
I´ve had both spline-shafts and spring discs replaced, (and the cogwheels the spline-shafts drive, as well as the spline inserts in the camshafts for good measure), and it reduced the noise a lot, but not completely.
It is 1.5 - 2 days work for two mechanics, one of which needs to have M training.
Also note, if you get this done the Vanos will sound awful for a few days or so, until all air that gets trapped inside is pushed out by the oil flow.
Then the sound gets very much better.
Vanos niose in the E60 M5 ***********************
The good news on Vanos noise aestetics is that the E60 M5 has horrible Vanos noise at idle, far worse than a non-upgraded E39 M5. I think this will bring Vanos noise into fashion as the "Sound of the M engine". ;-)
David
What does Vanos do? ****************************
The Vanos units change the timing reationship between crankshaft and the four separate camshafts. This directly controls valve timing both on intake and exhaust. This is what gives the wonderful flat torque curve. This is what gives the wonderful full-load-high-RPM engine note. This is what makes an S62 engine an S62.
Two kinds of Vanos noise in the E39 M5 ****************
There are two kinds of Vanos noise.
The first kind is loud rattle only heard at startup and stops within a minute. This is fixed by installing the Vanos oil pressure accumulator.
The second kind is loud rattle (like an old Mercedes diesel) that gets worse the warmer the engine is. This calls for replacing parts of the Vanos units.
History of extended warranty *****************
There has been several fixes on the Vanos system. In the US, BMW initially denied any problems, but later after pressure from owners (many of whom are members of this board) issued free Vanos oil pressure accumulator coverage until December 2003 / 3 years / 100000 km .
History of fixes **********************
First of all, on cars built up to November 2000, get the Vanos oil pressure accumulator installed. This is a compressed gas oil pressure vessel and a shutoff valve that takes high pressure oil (200 Bar) from both Vanos hydraulic pumps while the engine is running and stores it until the nest enigine start. There is an electromagnetic shutoff valve that keeps the pressurized oil in the vessel when the engine is stopped.
(very neat design, much better than the electrical priming pump they used before)
The installation procedure (takes about 1 day for 1 mechanic) is described in Service Bulletin 11 01 01 (661) issued March 2001.
This warranty action expires December 2003 / 3 years / 100000 km, whichever happens first, so hurry up.
This should take care of all Vanos noises that disappear by themselves a few seconds after starting the engine.
Most Vanos units will still make a bit of noise. If the diesel-sounding Vanos noise (after warm-up) is more than you are willing to accept, or if it keeps getting worse the more miles you put on the meter, you need to get some parts inside the Vanos units replaced. To get this under warranty, you need to be kind to your SA.
(btw there is no such thing as a completely noiseless Vanos, but in the case of my car subjectively 75% of the noise disappeared)
The production-dates and engine-numbers below are from BMW Germany recomending replacment of certain Vanos parts on S62 engines in case of loud rattles.
On M5 built before mid-July 2000 (engine number 60232305): replace
spline-shaft (BMW part number 11 36 4 781 417, 4 needed per engine) and
spring discs with support washers (BMW part number 11 36 7 833 218, 4 needed per engine).
Built after that, but before mid-September 2001 (engine number 60572609): replace just the spring discs with support washers (BMW part number 11 36 7 833 218, 4 needed per engine).
Built after that: everything ok from the factory.
I´ve had both spline-shafts and spring discs replaced, (and the cogwheels the spline-shafts drive, as well as the spline inserts in the camshafts for good measure), and it reduced the noise a lot, but not completely.
It is 1.5 - 2 days work for two mechanics, one of which needs to have M training.
Also note, if you get this done the Vanos will sound awful for a few days or so, until all air that gets trapped inside is pushed out by the oil flow.
Then the sound gets very much better.
Vanos niose in the E60 M5 ***********************
The good news on Vanos noise aestetics is that the E60 M5 has horrible Vanos noise at idle, far worse than a non-upgraded E39 M5. I think this will bring Vanos noise into fashion as the "Sound of the M engine". ;-)
David