My guess about chunks missing from "O" rings would be most damage to "O" rings, besides age, is directly caused by installation. A tougher materiel would be more resistant to installation damage but still not impervious. You must lubricate the "O" ring and the bore before installation and if it does not assemble smoothly the "O" ring should be removed and inspected for damage. If the "O" ring is not exactly the correct size then that can also contribute to installation damage. Obviously "O" ring damage is not a common problem unless the PPR has been disassembled or we would be seeing a lot more cars with pressure problems. There are a lot of Deloreans out there with original units that have never had their PPR's touched and are working just fine. For further information there is a lot of stuff available about this subject all over the Internet. Start with "O" ring manufacturers and their advice on installation procedures and fitting of the correct size "O" rings and how to handle them. NASA learned how critical handling "O" rings can be!!!! David Teitelbaum --- In dmcnews@xxxxxxxxxxxxxxx, "Delorean3760" <Delorean3760@...> wrote: > > I had the same exact problem, same O-ring, same place , I recall the group saying to put in a Viton O-ring (may not be the proper spelling) I used to keep 10 or so in the glove box just to fix the warm start problem. Very frustrating.......I fixed the problem s ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: dmcnews-digest@xxxxxxxxxxxxxxx dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/