Subject: Re: Rajaie , Question Author: rajaieq as Rajaie (moderator) : 205 posts Posted on: 2008-02-26 16:35:41

Many 99-00 M52TU owners have replaced their vanos with a new OEM vanos and had the idle problem return in 20k miles. I removed and inspected OEM seals from my car at 20k miles. The O-rings were fully failed; full compression set (flat top and bottom surfaces) and almost complete loss of elasticity (turning into plastic).
I inspected new OEM pistons from my car after 3k miles and they had a notably looser fit than when new. This is an indication of notable compression set. I had installed them into a used vanos.
When I first fixed my vanos with new OEM pistons (from a new OEM vanos) I noticed my performance improvements disappeared after 6k miles.

The OEM vanos piston seal Buna O-rings are completely not compatible with the engine environment. It is not a matter of wear and tear.

The Beisan seals Viton O-rings have a shelf life of 6 years. Once they are installed they are protected from sunlight and covered with oil to protect from Oxygen.
When you purchase them, they might be as much as 1 year from cure (manufacture).
I plan on providing the seals kits indefinitely.

Hope this helps.

Rajaie
528i 5sp 06/00

• Rajaie , Question - oembimmerparts 2008-02-26 15:14:23 (225 views)
  • Re: Rajaie , Question - Rajaie 2008-02-26 16:35:41 (191 views)
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