I think the Oil/Air separator is the likely culprit, coupled with a less than optimal cap seal.
For those who don't know, ......all engines get some form of blow-by and it needs to exit somewhere. In the old days (or the old-old-old days as my kids would define it) the gasses vented overboard, either damaging the ozone layer, or dripping on your garage floor. Forward to the old-old days, and in the Nord (carbs and I assume Spica)the pressurised air is fed back into the inlet path via the separator to give it a second chance at exiting via the exhaust. As this burned air is oil-laden, the separator removes some oil and feeds it back to the oil system. It's a basic and crude device barely up to the task, but it helped pass the regulations of the day. If it gets clogged with carbon, the pressurised air will seek another form of relief to atmosphere. Oil cap is a good candidate, or if blow-by is sufficient (worn rings) it could pop the dipstick out, or blow a gasket. Highly unlikely an engine would get bad enough to damage an oil filter though. Some people install a more efficient separator (a.k.a swirl can) to better remove the oil. Some modern engines, particularly turbos, benefit from the installation of a swirl can plumbed back into the engine, to reduce the oil and carbon building up on the turbo vanes. If your racing class allows it (because it's illegal most everywhere for road cars) you could vent the gasses overboard. To maximise performance, you don't want this oxygen deprived air back into the inlet. I once had to drive a tired Alfa a few thousand KMs. The engine was 'burning' more oil per KM than I could carry for the trip, and fouling plugs making it un-driveable. So I quickly fabricated an overflow container/catch can, installed it onto the separator port, plugged the manifold inlet and off I went. Every 200km or so I emptied the catch can contents back into the engine and continued on. By the end, 200km was only just enough of an interval ;-) Beatle Bored and Alfaless in Oz.......... -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Brian Shorey Sent: Saturday, 4 February 2012 5:19 PM To: 'John Palumbo'; [email protected] Subject: RE: [alfa] Oil cap leaking >This is just an idea keep in mind, but I can't imagine a clogged oil air seperator would make a oil filter explode or oil cap to leak for that matter. I had this very problem on my Berlina 6 months ago. Diagnosed by Michael Wrigley and Ian Anderson. Oil cap was leaking big time, even had a brand new one I put on, tightened the tabs etc, nothing helped. Mine was pi$$ing large amounts of oil into the #1 spark plug well. Cleaned the separator and the problem went away. bs -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected] -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
