---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 05/17/16: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:54 AM - Re: 912 o-rings (D L Josephson) 2. 06:28 AM - Re: 912 o-rings (Roger Lee) ________________________________ Message 1 _____________________________________ Time: 12:54:13 AM PST US Subject: RotaxEngines-List: Re: 912 o-rings From: D L Josephson On 5/17/16 12:02 AM, RotaxEngines-List Digest Server wrote: on 912 O-rings > From: "Roger Lee" > > > There is an "O" ring at the base of the cylinders. See Parts manual section > 72-20-00 pg. 16. Item #14 and part #250510. It is a Viton 87mmx2mm "O" ring. I > buy my "O" rings from Maryland Metrics Thanks Roger and Richard. Viton or Buna-n? David ________________________________ Message 2 _____________________________________ Time: 06:28:27 AM PST US Subject: RotaxEngines-List: Re: 912 o-rings From: "Roger Lee" Viton Copy and paste info: Viton and Buna seals have several very crucial differences that make them especially well suited to certain applications. While both Viton and Buna seals both serve as great sealing options at moderate temperatures, Viton is far superior to Buna for high temperature applications. Viton seals provide an indefinite seal for temperatures up to 400F, and for temperatures up to 600F they offer an excellent seal for more than 48 hours. Buna on the other hand is only effective up to 250F. However, Buna seals provide a low temperature sealing option with effective sealing down to temperatures of 22F, while temperatures below 5F render Viton seals ineffective as they become quite hard and inflexible. Along with temperature, other environmental conditions differentiate these two seals. An exceptionally broad range of chemical resistances make Viton seals a perfect option for most applications involving oils, fuels, and mineral acids, and these seals also boast excellent resistances to oxidation, ozone, UV exposure, weather, fungus, and mold. While also boasting some chemical resistances, Buna is much less universally resistant than its Viton counterpart suffering degradation from weather and ozone exposure. For most circumstances, however, this is not an issue, and Buna seals also offer the benefit of superior abrasion and tear resistance making them more suitable for more heavy duty industrial applications. - See more at: http://www.humphrey-products.com/content/viton-vs-buna-which-seal-for-your-applications#sthash.tnt528Om.dpuf -------- Roger Lee Tucson, Az. Rotax Instructor & Rotax IRC Light Sport Repairman Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=456330#456330 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.