DeTomaso Mailing List: November 97, Message #97
     



From: 	<KVERGES@figdav.com>

Subject: Re: Oil Guyser From Valve Cover Breather

Date: 	Mon, 3 Nov 1997 17:22:35 +0000



All,



I have an irritating oil "leak" that I am pretty sure originates from the breather on the drivers side valve cover.  I have the  simple "half-twist" breathers with the tabs that go in the slotted hole of the cast valve covers with "DeTomaso" on them.  The breather is in turn connected to the air cleaner.  Passenger side breather goes to functional PCV valve.



No problems on the street.



However, at last weekend's vintage race (TWS), we switched track directions with a lot more high-rpm sweeping turns to the right, which I theorize combined with the oil being hot and pumped up into valve covers, allowed oil out around base of the breather.  Big mess and a couple of black flags until I started short-shifting.



I already have restrictor pushrods (Smith Bros with .090 feed holes) in place and run hydraulic lifters.  I want to be sure valve springs get cooled and lifters get oil, so cuttting off more oil internally seems a problem.



I was thinking about pulling valve covers, modifying them for positive seal breather or welding on an AN-10 or 12 fitting, and putting a breather up high and relatively centered on the engine, but this could be unsightly.  I could have a vented catch tank, but I would have to empty it at least every session and it might fill during the session.  BTW, the engine is tired enough that I probably have a bit too much crankcase pressure. Last compression test was good at 180 psi +/- 5 psi on all 8, but I haven't done a leakdown test.



Then I thought about sealing valve cover altogether and venting crancase through a hole in the intake manifold, venting directly from the "V," which presumably can't fill up with oil.



Anyone have similar problems and solutions/suggestions?



THX



Keith