Sounds like it may be more than carb problem, unless a lower secondary butterfly is stuck open - just slightly will cause what you are talking about, and my 2nd 300C had this happen, and it seemed funny why car would not idle - the shaft had seized just enough from lack of use, even though in fairly dry climate here. Another more fairly common reason why a rebuilt motor will not idle is a vacuum leak somewhere - could be a gasket at base of carby, the line/fitting that goes to power (vacuum) assisted brakes/cannister, or worst, intake gaskets on underside of intake manifold, which can happen if heads milled, and intake not matched to them. For motor not to idle below 700 rpms indicates pretty major leak, although high duration cam may raise minimum idle speed above former usual lower figure, but this does not sound like cause here. Some people try using squirt bottle to put little gas around carb bases to see if this fixes/helps - if it does, it is gasket at base of carb. Also if brake booster's internal rubber vacuum/gasket fails with age, and alllows motor vacuum through, that will also lean out motor - can test this by blocking vacuum line to booster - if no change, this likely not the problem. Christopher in Australia >From: "Wayne Graefen" <wgraefen@xxxxxxxxxxxxxx> >To: "Intl 300" <Chrysler300@xxxxxxxxxxxxxxx> >CC: <Dennis57300@xxxxxxx> >Subject: [Chrysler300] Urgent help needed - 300C TSB >Date: Tue, 11 Sep 2007 20:30:28 -0500 > >Dennis57300@xxxxxxx , Dennis Goodemote has his rebuilt 300C 392" sitting >on a dyno at a shop and can not get the rebuilt carbs to idle at all. >Several hundred rpm too high. > >I think he needs to go through linkage and carb adjustments from the 300C >tech bulletin that was part of the '57 TSB set. I don't have mine any >where near me tonight. The individual TSB I'm talking about is the >approx. 30 pages of info regarding the 300C which is above and beyond what >got into the factory shop manual. Of those 30 there is probably 10 pages >on carburetion. > >Dennis is just south of Buffalo, NY. Hoping someone has the TSB scanned >or can fax it to Dennis or drive over with it if you are that close. The >working hours screwing around with the engine on the dyno are at $60 per >and are adding up fast. > >Dennis has not gotten back to me re. whether he has a fax so email him if >you need a fax or phone number to make this happen. > >Wayne > >[Non-text portions of this message have been removed] > _________________________________________________________________ Advertisement: See what's Hot in new Live Hotmail http://ninemsn.com.au/share/redir/adTrack.asp?mode=click&clientID=810&referral=Hotmailtagline&URL=http://www.livehotmail.ninemsn.com.au/ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto:Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/