quickWS6

I was about to put my Metco valve cover breather on the car tonight, but a mechanic friend said something that has made me stop and find out something first. He said that on the PCV system, using the valve cover breather would vent out too much crankcase pressure, and hurt the engine. He said the PCV system was regulated to let the right amount of pressure be present at all times. Now, I don't think I have any oil consumption problems yet, I was just putting it on for insurance and because it looks so good. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Will putting it on hurt my engine in any way? Thanks a lot for any insight into this.

BYE RICE

iTrader: (2)

"old wives tale" mayby.
The only pcv system that I've seen do any damage was on a early '90's Taurus.It blew out the front seal. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
I like my Metco.It looks nice,too.

WayneSS01

Check out the link in this thread https://ls1tech.com/ubb/cgi-bin/ulti...=001719#000000

Dipstick

I don't see any problem as long as you keep the stock PCV valve in place to regulate the air going into the TB.

NicD

iTrader: (7)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Dipstick:
<strong>I don't see any problem as long as you keep the stock PCV valve in place to regulate the air going into the TB.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Since when does the PCV regulate airflow into the TB?

cobray

Dude check this link out.
http://service.gm.com/gmtechlink/Mar...les/blowby.htm

With the Metco Breather, and a manometer I made with help from the above link, I registered 0 crankcase pressure up to 3000 RPM.
I think if you waiting for your seals to leak you are kinda losing the preventive benefit of the breather in that it will help prevent the seals blowing in the first place.

Pro Stock John

iTrader: (34)

That is a great link, how much is a manometer?

I have a pet theory that I would like to test. I think the LS1's stock have a lot of crankcase pressure.

I have run Metco breathers and the alleviate crankcase pressure. I don't anyone can tell me why it's bad to run one on our motors except from a pollution standpoint.

quickWS6

Thanks guys. I read the report, but it sounded like not to put it on unless you were having oil leaks or the like. So, should I not put it on or put it on and not worry about it?

cobray

It is my understanding from reading the manufacturers web site that a crankcase breather will not affect the operation of the PCV system. I would think a test that would validate it would be to check the PCV valve with and without the breather on it, to see if there is a difference.

Im in the middle of cleaning the engine of my girlfriends 325i...butIm going to try to test this later today.

Ive never checked to see where the PCV valve is on my LS1 (ive only had it for about a month)..

Im not trying to doubt anyone...Im not 100% sure that running the breather is bad. Could anyone else comment on this?!!?1

cobray

Would like to add one thing, Ive had the breather on my car for the last 1000 miles and I have consumed 0 oil. I only have 2150 miles on it now.
It is my understanding also that the crankcase breather is bad for emissions, since it will let excesss crankcase pressure pass thru it. I guess the key word here is excess.
Like all real Americans, I consider emissions to be un-american as the Taliban.

I find it interesting that your oil consumption changed...

<small>[ June 22, 2002, 01:07 PM: Message edited by: cobray ]</small>

383LQ4SS

iTrader: (33)

I remember seeing the article by Ray Bohacz. He basically said that the fumes and gases that a running engine creates are corrosive and bad for engine oil and internals. And the PCV would evacuate these gases so corrosive compounds dont build up in the oil.

Personally I think running a breather is great..just change your oil religously at 3000 and use synthetic or synthetic blend. I have used one for 3 years on my SS with no related problems.

cobray

http://www.metco-inc.com/valvecvr.htm

excerpt from above link

Q. Why should I use an open-element Valve Cover Breather?
A. Crankcase pressure has long been considered detrimental to engine performance and gasket sealing. As pressures increase through performance and age gaskets often begin to leak. By venting the crankcase to atmosphere those pressures are greatly reduced.

Q. Will my PCV Valve operation be affected?
A. No. The PCV will still open and function should crankcase pressure be encountered.

Dipstick

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Since when does the PCV regulate airflow into the TB?</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The PCV valve line runs to the high vacuum side of the TB. The other hose on the TB is the fresh air to the valve cover. Try pulling the line from the PCV valve off and see what it does to your idle.

The Metco or any other breather will let unrestricted air into the valve cover during high vacuum conditions and vent excess crank pressure when there is more than the PCV valve can eliminate, such as at low vacuum(WOT)times.

Terry Burger

iTrader: (4)

Most mechanics don't know much about cars. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

MY99TAWS6

iTrader: (3)

Ray bohaz I think his name his responded to a post in high tech performance and said never put a breather on a street car as he said race cars don't matter as they are run at w0t..at street vacuums having a breather will defeat the purpose of the pcv and let blowby get into oil and stuff which would be bad for engine I guess..I haven't used one since.I had lots of oil coming thru my intake before..I tried vertical pcv mod with stock pcv valve and lately went to the new pcv mounted stock location with 10/30 amsoil.I did my oil change about 1000 to 1500 miles ago and haven't noticed my oil go down much at all..still not even at add yet..was going thru probably a quart or so every 1000 before.I do drive my car in the high rpm range quite a bit..so anyone who really knows his stuff have anthing more to say on this..I don't care about emissions right now..already took off egr and air pump..hokey crap.