Jase007
11-11-2012, 01:07 PM
I replace the vanos seals on my '00 BMW E39 528iT a few years back and thought this might be helpful to any that have single / dual vanos motors (most all inline six cylinders and V8s from '99 up). Not covering the V8 repair here.
My car had the typical idle oscillation and engine "jolts" when cold weather struck and once warmed up ... ran like a champ all day. Being a 5 speed manual I simply heel and toed the gas / brake and was living with it ... no big deal.
For those that don't know and own a BMW with the crappy OEM buna seals [double vanos ] see quote below and read up on at www.beisansystems.com.
"Vanos" is BMW's name for its variable valve timing units. Vanos units take on various shapes and design according to car year and model (engine model). The vanos discussed here is BMW part # 11-36-1-440-142. It's a double vanos; meaning both the intake and exhaust valve timing is varied. This vanos unit is part of BMW 6-cylinder engines M52TU, M54, and M56. These engines were incorporated into a wide range of car models during years 1998-2006.
They are found in the 3-series E46 98-05, 5-series E39 99-03 / E60 & E61 02-05, 7-series E38 98-01 / E65 & E66 02-05, Z3 E36 98-02, Z4 E85 02-05, X3 E83 03-06, X5 E53 00-06.
This vanos has been experiencing a failure. It has been diagnosed that the failure is due to deterioration of the vanos piston seal O-rings. It has been determined that these O-rings are made from Buna (Buna-N, NBR, Nitrile). Buna is a very common O-ring material, but is limited in its temperature and chemical resistance characteristics. Unfortunately it is fairing quite badly in the vanos/engine environment. The O-rings have been found to harden, shrink, and have flat surfaces. This deterioration is causing the O-rings to loose their functional characteristics and thus cause the vanos to fail. BMW has been engaged regarding this matter, but has elected to not address the issue, "No further development will be done". New (rebuilt) vanos units are being sold with the same Buna O-rings. BMW does not provide the vanos piston seals/O-rings as a separate part.
My repair: (not going to do a writeup how-to b/c Rajaie's site is all you need.)
I installed mine over a weekend ... here are some pics:
I had issues with fan clutch nut and didn't want to take an air chisel to it as was recommended by a BMW tech friend so I got the correct tools from ZdMak.com. Quality is pretty good for what they cost and I put some leverage on them to get the $%#&% fan clutch nut off.
(tools are inside jack handles that I needed for leverage to get that nut off )
33671
Fan / shroud out and valve cover off M52TU 2.8L. Lovely varnish from previous owner using BMWs extended mileage changes
33672
Vanos unit off, pistons removed, looking into cylinder bores where pistons ride:
33673
New viton and teflon seals installed on intake and exhaust pistons. Old buna seals were hard as S$%T and worthless b/c allowed oil to bypass piston. Felt like solid plastic when removed. New setup is brown viton O-ring under the grey teflon seal that rides against cylinder bore. Pistons are held back to back for picture.
33674
While I was in there I replaced the high pressure vanos oil feed line. It is a swaged setup and the one on my car was sweating oil pretty good.
33675
cylinder bore shot:
33676
another:
33677
Cold start problems were gone after three days of sub 35F starts and ~ 150 miles. No idle oscillation causing the car to shut off. Vanos pistons operated better after a break-in [I was still getting some jolts / oscillations right after repair] and after the ~500 break-in miles everything worked as designed.
Seals only cost ~$60.
BMW will only sell you a replacement VANOS unit for around ~$400 and then charge 3-4 hours labor = $800. Or, they won't repair at all and will use a software patch to mask the failing seals by creating a smooth idle, etc...
The kicker on the replacement vanos unit from BMW .. it is a re-manufactured unit with the same crappy buna seals that will fail again in short order.
If you can change your oil you can easily accomplish this repair in a weekend.
* Note there are also vanos "rattle" (occurs on startup) kits available from www.beisansystems.com now. These were NOT available when I did my repair. If you can live with the rattle, then I'd just do the seals.
Net benefit: normal cold start / warmup, more torque due to working variable valve timing operating correctly, some report better mileage.
Cheers.
My car had the typical idle oscillation and engine "jolts" when cold weather struck and once warmed up ... ran like a champ all day. Being a 5 speed manual I simply heel and toed the gas / brake and was living with it ... no big deal.
For those that don't know and own a BMW with the crappy OEM buna seals [double vanos ] see quote below and read up on at www.beisansystems.com.
"Vanos" is BMW's name for its variable valve timing units. Vanos units take on various shapes and design according to car year and model (engine model). The vanos discussed here is BMW part # 11-36-1-440-142. It's a double vanos; meaning both the intake and exhaust valve timing is varied. This vanos unit is part of BMW 6-cylinder engines M52TU, M54, and M56. These engines were incorporated into a wide range of car models during years 1998-2006.
They are found in the 3-series E46 98-05, 5-series E39 99-03 / E60 & E61 02-05, 7-series E38 98-01 / E65 & E66 02-05, Z3 E36 98-02, Z4 E85 02-05, X3 E83 03-06, X5 E53 00-06.
This vanos has been experiencing a failure. It has been diagnosed that the failure is due to deterioration of the vanos piston seal O-rings. It has been determined that these O-rings are made from Buna (Buna-N, NBR, Nitrile). Buna is a very common O-ring material, but is limited in its temperature and chemical resistance characteristics. Unfortunately it is fairing quite badly in the vanos/engine environment. The O-rings have been found to harden, shrink, and have flat surfaces. This deterioration is causing the O-rings to loose their functional characteristics and thus cause the vanos to fail. BMW has been engaged regarding this matter, but has elected to not address the issue, "No further development will be done". New (rebuilt) vanos units are being sold with the same Buna O-rings. BMW does not provide the vanos piston seals/O-rings as a separate part.
My repair: (not going to do a writeup how-to b/c Rajaie's site is all you need.)
I installed mine over a weekend ... here are some pics:
I had issues with fan clutch nut and didn't want to take an air chisel to it as was recommended by a BMW tech friend so I got the correct tools from ZdMak.com. Quality is pretty good for what they cost and I put some leverage on them to get the $%#&% fan clutch nut off.
(tools are inside jack handles that I needed for leverage to get that nut off )
33671
Fan / shroud out and valve cover off M52TU 2.8L. Lovely varnish from previous owner using BMWs extended mileage changes
33672
Vanos unit off, pistons removed, looking into cylinder bores where pistons ride:
33673
New viton and teflon seals installed on intake and exhaust pistons. Old buna seals were hard as S$%T and worthless b/c allowed oil to bypass piston. Felt like solid plastic when removed. New setup is brown viton O-ring under the grey teflon seal that rides against cylinder bore. Pistons are held back to back for picture.
33674
While I was in there I replaced the high pressure vanos oil feed line. It is a swaged setup and the one on my car was sweating oil pretty good.
33675
cylinder bore shot:
33676
another:
33677
Cold start problems were gone after three days of sub 35F starts and ~ 150 miles. No idle oscillation causing the car to shut off. Vanos pistons operated better after a break-in [I was still getting some jolts / oscillations right after repair] and after the ~500 break-in miles everything worked as designed.
Seals only cost ~$60.
BMW will only sell you a replacement VANOS unit for around ~$400 and then charge 3-4 hours labor = $800. Or, they won't repair at all and will use a software patch to mask the failing seals by creating a smooth idle, etc...
The kicker on the replacement vanos unit from BMW .. it is a re-manufactured unit with the same crappy buna seals that will fail again in short order.
If you can change your oil you can easily accomplish this repair in a weekend.
* Note there are also vanos "rattle" (occurs on startup) kits available from www.beisansystems.com now. These were NOT available when I did my repair. If you can live with the rattle, then I'd just do the seals.
Net benefit: normal cold start / warmup, more torque due to working variable valve timing operating correctly, some report better mileage.
Cheers.