The leaky (small) has finally got attended to.
You will not be able to see this leak unless the car is on hoist and you check from under the car. This vaccum pump is placed just infront of the firewall and at the back of the camshaft. However the symthoms of a leaky vaccum pump is quite easy to detect without putting the car on hoist. If you start your car in the morning and you see smokes from under the engine bay area or you can smell burning oil, then it's highly possible that you are having this problem.
The reason for the smoke and smell of burning oil in the morning is because the vaccum pump is located right above the exhaust pipe. Some motor oil will drip on to the exhaust pipe when you park overnight. The smoke & smell is the result of the hot exhaust pipe burning the fresh motor oil.
It's not a very serious issue but can be a bit irritating because of the smokes and smell of burning oil.
Up to now I have heard of many who just replaced the complete unit. But this is quite costly. Depending of availibility of stock (fast moving item) the price range is between RM750 - RM900 for an OEM unit. My check with Singapore for an original unit is SGD450
After studying a "faulty changed out" unit I find that the problem for the leak is actually due to harden/elongated O ring rubber seals. When you open up the unit the O ring cannot be reused. It would be a waste of time and money/labour if you refitted the old O ring. It will surely leak again very soon.
There are 2 O rings. One smaller which is the outer and a bigger one which is the inner seal. Check with
http://bmwfans.info/parts/catalog/ reveals that only the smaller O ring is available for sale. This will not solve the problem. Not sure why the larger O ring is not available. My guess is BMW wants you to spend big i.e. replace the entire unit.
I asked my mechanic/workshop to go hunting for this larger O ring and the good news is he has found the correct size.
The vaccum pump has today been serviced and refitted with the 2 new O rings. Hopefully this will work. I will monitor the situation over the new 2 -3 weeks to see if the problem is resolved.
Sharing this in the hope that our friends with N42/N46 engine will be able to save some money.
Stay tuned for updates.
