Vintage Mustang Forums banner

1 - 14 of 14 Posts

·
Registered
Joined
·
913 Posts
Discussion Starter #1
I was looking through engine pics on here and it seems quite a few of you have opted to go with a breather on that valve cover instead of running the pcv valve. Does it hurt anything to remove it?
 

·
Registered
Joined
·
3,323 Posts
Why? What benefit would you gain?
 

·
Gone but never forgetten
Joined
·
25,239 Posts
Only remove it if you don't care about your oil getting fuel contaminated and ruining your engine.

Even the OLD engines had a down draft tube. Just running a breather won't get the job done. You don't see them on race engines, because they basically dump the oil and rebuild the engine after pretty much every run. Street engines should have one if you want the engine to last.
 

·
Registered
Joined
·
913 Posts
Discussion Starter #5
Nothing other than a cleaner look. That's why I was wondering, I wouldn't want to remove it if it would cause any harm.
 

·
Registered
Joined
·
913 Posts
Discussion Starter #6
I see. I will leave it on there. I don't guess I really understand what a pcv valve does exactly.
 

·
Gone but never forgetten
Joined
·
25,239 Posts
I don't guess I really understand what a pcv valve does exactly
On any engine, you will get some blow-by past the rings. This blow-by is fuel vapors and exhaust fumes. Those vapors/fumes go past the rings during the compression and exhaust strokes. If these vapors aren't removed, they will churn in with the oil, and degredate the oil quickly.

The PCV (Positive Crankcase Ventilation) is a 1-way valve that will only allow air to travel one direction through it. It hooks to a vacuum source (from the intake manifold) and sucks fresh air from the breather in the other valve cover, down through the crank case and back out the other valve cover purging the valve covers, and crank case of these fuel vapors, and putting them back into the intake manifold to be re-burned.

Most modern carburators are calibrated to run with this "giant vacuum leak" that is the PCV system.
 

·
Registered
Joined
·
1,844 Posts
Another option for crankcase ventilation is to use the scavangers that plumb into the exhaust. If you mount the valves up high away from the heat they last quite a while and they scavenge even better than the vacuum of the engine....plus you don't contaminate your air/fuel mixture. I have run them successfully on several cars. My Shelby will not idle correctly without at least one of them hooked up and functional.
 

·
Registered
Joined
·
296 Posts
The PVC helps reduce engine oil leaks. I know that there are very few Mustang's that have crankshaft rear main seal's that leak, But just in case it might start to leak leave it in place.
 

·
Registered
Joined
·
904 Posts
My engine ran like crap because i had a breather on instead of a pcv valve (didn't know better at the time). Once i put a pcv valve on it ran 10000 times better, and its not really that less atractive. I found a sleek chrome one at kragen for like $11.
 

·
Registered
Joined
·
150 Posts
So should the hose coming from the PCV valve be connected directly into the intake manifold or connected to the carb.? Or does either one work?
 

·
Registered
Joined
·
146 Posts
For the record I run my PCV, but my question is why is there a breather on the other side? My PCV is on the pass side and my drivers side has a breather. If it's that important why not one on each side?

Don
 
1 - 14 of 14 Posts
Top