[Healeys] crank case ventilation

[Bob Spidell]

Hi Michael, 

If you mean the non-vented approach pulls more vacuum on the crankcase I agree. But, you're pulling unfiltered air in through other gaps (like around the crankcase seal). 

The 'sealed' PCV system works good on our cars, but it's not a PCV 'system' per se. A proper PCV system circulates filtered air through the crankcase, mixes it with blowby and sends it back through the intake manifold. 


bs 

-------------------------------- 
Bob Spidell - San Jose, CA 

----- Original Message ----- 
From: "Michael Salter" <msalter at precisionsportscar.com> 
To: "Bob Spidell" <bspidell at comcast.net> 
Cc: "Healey" <Healeys at autox.team.net> 
Sent: Wednesday, March 17, 2010 12:29:12 PM GMT -08:00 US/Canada Pacific 
Subject: Re: [Healeys] crank case ventilation 

Hi Bob, 
By installing an air intake filter on the valve cover you will be missing out on one great advantage of a PCV system for a Healey engine. 
A PCV system partially evacuates the crankcase and, in so doing, eliminates the flow of oil laden air through the rear main seal. I had a hidden PCV system on my BJ8 many years ago and it completely stopped a substantial rear main seal leak that was caused by wear on the crankshaft scroll surface. 



On Thu, Mar 18, 2010 at 2:21 AM, Bob Spidell < bspidell at comcast.net > wrote: 


That type/size filter is usually used on a PCV-fitted car as an intake filter on a valve cover. 
One possible problem with the PCV retrofit on a Healey is the PCV valve is usually fitted to draw gases through the 'T' fitting on the valve cover. An exactly correct PCV installation would have the T fitting removed and something like this on the valve cover so air would be drawn in through the valve cover and gases--including blowby and air from inside the valve cover that gets pulled down the pushrod holes--to be sucked into the intake manifold (i.e. a truly closed system). 

I've considered this for my car but haven't tried it. 


bs