Dan: I don't know the complete answer to that one so am forwarding it to the collective knowledge of the club for their input on transition dates from breather caps to breather tubes to PCV's I do recall cars of the 40's and 50's with just crankcase breather caps on the oil input drop tube really getting grubby from condensed oil fumes on top and sides of the engines, which then collected dust and really built up. Breather caps were routinely cleaned with solvent at oil change time and we really earned our nickname of grease monkey. Also, there were consistent black streaks in the middle of gray concrete roads from the accumulated oil vapors and drips. These were darker on the uphill side of grades as the engines were working harder. The first rains of fall hitting this grease really generated a slick road surface (still does). I believe this was the first and easiest pollution to get cleaned up with PCV's that ran the crankcase fumes back into the engine air intake system through a little foam filter that also plugged up. My wife claimed she could smell the exhaust fumes from my C-300 as she followed me in our minivan. Catalytic oxidation of unburned fuel and computer control of fuel-air ratio have really cleaned up the exhaust of modern engines. I got a citation from the Texas Air Quality Board when someone in Houston snitched on my turbo K-car Chrysler T&C that would emit a little puff of oily smoke after sitting idling at a stop sign due to worn seals on the turbo. I hadda get it fixed, even though it burned no oil to speak of. Nasty stuff, those crankcase and exhaust vapors and nasty citizens those snitches. MoPa'r to progress. Rich Barber Brentwood, CA C-300 DH483@xxxxxxx wrote: > Rich Barber, > > Maybe you can put this into perspective for me. I understand the need > for a pcv valve, or on the older cars a breather tube. When did > Chryslers (and cars in general) start using breather tubes? How were > fumes vented prior to this? > > Thanks > Dan Hecker > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Yahoo! Autos. Everything you need to know about buying or selling a car. FREE Quotes, 360° Tours, Research, Blue Book, Compare Vehicles, Buy Used http://us.click.yahoo.com/kEZsdA/bwnGAA/YiGOAA/8LmulB/TM --------------------------------------------------------------------~-> 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 Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> 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/