Hot Rod Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
131 Posts
Discussion Starter · #1 ·
I just got a pcv valve put on my truck. I'm a bit confused on why he put a oil plug , instead of an oil breather in the right side valve cover.








Will this be alright?

Thanks guys.
 

·
Registered
Joined
·
906 Posts
fastandloud,

I California(where I live) in order for this to be smog correct. There needs to be a hose coming from the drivers side vent hole to a hole inside the air filter next to the carb. So as to draw in clean air and to keep the system "closed" in case there is a problem with the positive crankcase ventilation valve.

Scholman
 

·
Registered
Joined
·
131 Posts
Discussion Starter · #7 ·
fastandloud,

I California(where I live) in order for this to be smog correct. There needs to be a hose coming from the drivers side vent hole to a hole inside the air filter next to the carb. So as to draw in clean air and to keep the system "closed" in case there is a problem with the positive crankcase ventilation valve.

Scholman
Yeah, I don't have emission testing of any kind. So, its cool.

Tech!:thumbup: Yes over the fence LOL:D
Thanks guys.
 

·
Registered
Joined
·
15,628 Posts
I just got a pcv valve put on my truck. I'm a bit confused on why he put a oil plug , instead of an oil breather in the right side valve cover.








Will this be alright?

Thanks guys.
This is set up correctly for the type air cleaner you have. It is not necessary to allow the crankcase to breathe and in California that's illegal. The PCV will keep a vacuum on the crankcase pulling the blow by out.

If you go to a breather type cap it needs to be the hose connection type not open to the atmosphere. A hose is then connected between the breather cap and the air cleaner housing. Since you have a open style air cleaner the hose would need to connect inside the filter element; that exposes it to the possibility of a backfire igniting the blowby gasses resulting in a crankcase explosion. For your type air cleaner a fire trap needs to be installed over the tube end. The factory solves this problem by encasing the filter inside a metal housing where the vent tube exits vented blowby intakes fresh air outside the filter element but inside the housing thus using the filter as a fire stop.

Bogie
 

·
Old(s) Fart
Joined
·
6,077 Posts
This is set up correctly for the type air cleaner you have. It is not necessary to allow the crankcase to breathe and in California that's illegal. The PCV will keep a vacuum on the crankcase pulling the blow by out.
Sorry, but I disagree. First, it IS necessary for there to be some sort of air inlet for the PCV to function properly. The only way to evacuate the crankcase fumes is for them to be replaced by fresh air. Suck on a straw with the other end capped and you get no flow.

And as for the setup in the photo being "correct" for that air cleaner, sorry but that is also not correct. Flip that air cleaner over and you'll find a knockout on the underside, inside the filtered area. When new, this air cleaner came with a bolt-on elbow SPECIFICALLY for this purpose. If you needed a closed PCV system, the instructions (which usually were just thrown away) told you to remove the knockout and install the elbow and gasket. This provided a fresh air port that was supposed to routed to the breather cap in the valve cover.
 

·
Registered
Joined
·
15,628 Posts
Sorry, but I disagree. First, it IS necessary for there to be some sort of air inlet for the PCV to function properly. The only way to evacuate the crankcase fumes is for them to be replaced by fresh air. Suck on a straw with the other end capped and you get no flow.

And as for the setup in the photo being "correct" for that air cleaner, sorry but that is also not correct. Flip that air cleaner over and you'll find a knockout on the underside, inside the filtered area. When new, this air cleaner came with a bolt-on elbow SPECIFICALLY for this purpose. If you needed a closed PCV system, the instructions (which usually were just thrown away) told you to remove the knockout and install the elbow and gasket. This provided a fresh air port that was supposed to routed to the breather cap in the valve cover.
Yes all of that about the air cleaner is true, so is the risk of a crankcase explosion. As for breathing, Ford has dead ended PVC in California forever it seems. The blow-by feeds the suction if it passes that much, other wise the crankcase just operates under a vacuum which helps with ring sealing. Aside from that on a street engine there is no need to vent to the atmosphere, they are not trying to vent fresh air into the enigne the PCV is there to prevent blow by from entering the atmosphere.

If you're racing then it's a different problem where this arraingement will not be satisforctory.

His current set up is just fine, not my preference, but it's fine. I never use those open air filters on the street, I find it's tough to improve on what the factory used for carbs and TBI with an enclosed round filter element wih a thermostatic and vacuum switched air source that draws hot air off the exhust when the engine is cold then closes that to draw cold air from behind the grill when the engine is warmed up. These, at least for GM, then supply an air source to the crankcase with the PCV at the other side. All these hot rod air filters do is to let the engine draw under hood hot air all the time, if he's worried about horsepower it's probably costing 10 or 15 at red line since power goes down quickly as inlet air temp goes up. So these things may look cool, but looks aren't everything.



Bogie
 

·
Registered
Joined
·
131 Posts
Discussion Starter · #12 ·
Well guys, I just now put a push on breather on it as recommended to me earlier. I sure hope nothing explodes?

As far as emissions into the atmosphere, there is NO emission testing where I live, so that doesn't concern me.
 

·
TAKE A KID TO A CAR SHOW
Joined
·
2,865 Posts
I feel that a closed crank case ventilation system might get rid of blow by pressure but is lacking in getting rid of contaminants, Moisture, acids, gas, etc, and a breather will help in that respect,and if blow by over powers the vacuum on the pcv the breather will also act as an exit for the extra blow by pressure!


Get a breather you can put a tube on and run it to the air cleaner! On the opposite valve cover as the PCV. To each his own! Run what you want just stay within the laws of your area !

What years your vehicle?

Bogie states a closed crank case is not his preference!!!! But its fine for the street:thumbup: Its not my preference either!!! I'd run a breather till the law told me to change it over LOL!

Jester
 
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top