Vanos Seal Replaced

Ever since I got the car, I've noticed that the car has this slight hesitation when stepping on the accelerator or when holding the rev at a low 1.5 ~ 2k ie low end torque. After much researching and reading, one of the possible suspects would be the Vanos seal.

The vanos seal is a pair of O-rings that as far as I understand is part of the vanos and once it gets old, it harden, gets brittle and screws with the camshalf timing and will result is higher fuel consumption (as the camshalf if not running at the correct most optimum timing) and also lost of torque (both low and high end when the vanos kicks in).

Instead of just replacing the seals with OEM BMW stuff, I decided to use the Beisan Seals. It is a 3rd party company and apparently much better than the original seals. People around the world swears by it... so I'm pretty comfortable with this choice.

It came in this packing for single vanos

2 replacement o-rings

Unfortunately, while opening the head, it looked like the valve cover gasket and bush was also worn out. Another sign that this hadn't been replaced though the recommendation is to replace it every 100,000km. Black oil was leaking all over, so change that also lar....

Copied this picture off the web - only replaced a few of these

Camshalf timing was off just very slightly - not as bad as I've seen some sample pictures before on the net...

vanos camshalf and timing chain at the bottom

... so, I wonder if my car was all ok all along? After taking of the vanos unit....

... and removing the o-rings, this is how the existing one was...

How hard and brittle the o-ring was...

So how actually does the vanos work? The electric signal from the computer box should relay through the cable (bottom left) to push more oil into the camcover (the thinngy that looks like a cylinder in the middle). This then presses the vanos to push or pull the extra cog within and this is how the improve timing / vanos kicks in. Or at least this is what i learn from a crash course from the mechanic. :)

Picture borrowed from iridiumengineering.co.uk

It is A LOT of work... a lot of things got to be dismantled including 1 side of the cabin filters, the engine and valve cover, the coolant (or water) needs to be released before the thing can be dismantle. And if you also had a screwed up valve cover gasket and bush like i did, it also requires some surface cleaning before the new gasket can be put on. All in all 4 hours of work.

Can I feel the difference? Actually yes! The car is not as hesitant as it was before and it's a bit more responsive. But the seals take about 300km to break in. So will only know the full potential in a few weeks time... fingers crossed for a better response and better fuel consumption. :P

To read more on Beisan or Vanos: http://www.beisansystems.com/