PCV valve-What to do when removing stock air cleaner and install chrome one?

[Guest]

I just installed an aftermarket chrome air cleaner to replace the stock set-up? What should I do with the PCV connection that was going to the air cleaner set-up from the pass. side valve cover? Should I plug it off? I don't think it serves in particular function since I live in a state that is not worried about pollution control.
THanks for the insight.
Chad

 

[IowaMike]

Most of those have an adapter kit that is sold separately.

 

[chuck]

They do have a function, it will keep your eng. from sludging up. Anyway hook it up to the bottom of the air cleaner inside the filter ring. If you look closely you should be able to see a knock out for the connector

 

[Skuzzlebutt]

If you can't connect it to the air cleaner you need to find a filtered cap to fit in the hole in the valve cover.
Do you have a PCV valve at the oil filler cap connected to the base of the carb?

 

[Guest]

[quote author=Skuzzlebutt link=board=5;threadid=17197;start=0#msg131246 date=1052331164]
If you can't connect it to the air cleaner you need to find a filtered cap to fit in the hole in the valve cover.
Do you have a PCV valve at the oil filler cap connected to the base of the carb?
[/quote] I am not sure if there is a PCV valve at the oil filer cap connected to the base of the carb. I will have to check it out tonight. What should I do if there is one? What should I do if there is not one? Thanks for the tips.

 

[BwoncoHowie]

[quote author=Chad link=board=5;threadid=17197;start=0#msg131259 date=1052332804]
[quote author=Skuzzlebutt link=board=5;threadid=17197;start=0#msg131246 date=1052331164]
If you can't connect it to the air cleaner you need to find a filtered cap to fit in the hole in the valve cover.
Do you have a PCV valve at the oil filler cap connected to the base of the carb?
[/quote] I am not sure if there is a PCV valve at the oil filer cap connected to the base of the carb. I will have to check it out tonight. What should I do if there is one? What should I do if there is not one? Thanks for the tips.
[/quote]

The PCV system is one of the few emission controls that is actually good for your engine DONT DISABLE IT. I don't know what year you are working on but it is important to have a PCV Valve attached to an intake manifold vacuum source plugged into either a valve cover or oil filler cap with the opposite valve cover letting fresh filtered air into the crankcase. Do like Chuck says and get the kit and hook up the air cleaner hose.

BH

 

[77Mule]

I have mine running from the pass side valve cover up to the front of the carb and plugged into it. Thus the gases go directly into the intake manifold then vacume sucks it into the firing chambers. You want the escapes gases to go into the manifold or carb so taht any unspent gasoline fumes will get a chance to burn up. This is not for emissions as much as it is to keep petrol from collecting in your oil pan.

 

[Broncobowsher]

The PCV valve should be located in the passenger side valve cover and goes to the base of the carb or the intake.

What I think you are referring to is the breather. It lets fresh air into the engine as the PCV sucks the stale air out. It is also a vent for sustained full throttle driving where there is not enough vacuum for the PCV to suck.

The original went to the aircleaner. Either to the clean side or through a little filter on the dirty side. Most aftermarket aircleaners have a knockout to mount that fresh air hose. If that doesn’t work, a filtered oil fill cap is available.

Do not use a sealed oil fill cap. You need a vent for the crankcase to let fresh air in and maybe a little stale air out if you pull a long grade with your foot to the floor.

 

[Guest]

[quote author=BwoncoHowie link=board=5;threadid=17197;start=0#msg131266 date=1052334287]
[quote author=Chad link=board=5;threadid=17197;start=0#msg131259 date=1052332804]
[quote author=Skuzzlebutt link=board=5;threadid=17197;start=0#msg131246 date=1052331164]
If you can't connect it to the air cleaner you need to find a filtered cap to fit in the hole in the valve cover.
Do you have a PCV valve at the oil filler cap connected to the base of the carb?
[/quote] I am not sure if there is a PCV valve at the oil filer cap connected to the base of the carb. I will have to check it out tonight. What should I do if there is one? What should I do if there is not one? Thanks for the tips.
[/quote]

The PCV system is one of the few emission controls that is actually good for your engine DONT DISABLE IT. I don't know what year you are working on but it is important to have a PCV Valve attached to an intake manifold vacuum source plugged into either a valve cover or oil filler cap with the opposite valve cover letting fresh filtered air into the crankcase. Do like Chuck says and get the kit and hook up the air cleaner hose.

BH
[/quote] It is a 73 302 V8.....Just to let you know what I am doing....I am replacing the stock air system with a chrome aftermarker system (adds the ability to look into/work on the engine). I removed the hose from the PCV valve on the passenger side valve cover. I am not sure about a connection on the other side at this point from the oil filler cap to carb. I don't think there is a knock out on the new air cleaner, but I will look. All messages have been helpful...please continue with any or all input.

 

[Guest]

[quote author=Broncobowsher link=board=5;threadid=17197;start=0#msg131275 date=1052335262]
The PCV valve should be located in the passenger side valve cover and goes to the base of the carb or the intake.




What I think you are referring to is the breather. It lets fresh air into the engine as the PCV sucks the stale air out. It is also a vent for sustained full throttle driving where there is not enough vacuum for the PCV to suck.

The original went to the aircleaner. Either to the clean side or through a little filter on the dirty side. Most aftermarket aircleaners have a knockout to mount that fresh air hose. If that doesn’t work, a filtered oil fill cap is available.

Do not use a sealed oil fill cap. You need a vent for the crankcase to let fresh air in and maybe a little stale air out if you pull a long grade with your foot to the floor.

[/quote] I think you have hit it on the head. That is exactly what I am looking for. I will look at it more intensely. Thanks for your help

 

[77Mule]

BH
It is a 73 302 V8.....Just to let you know what I am doing....I am replacing the stock air system with a chrome aftermarker system (adds the ability to look into/work on the engine). I removed the hose from the PCV valve on the passenger side valve cover. I am not sure about a connection on the other side at this point from the oil filler cap to carb. I don't think there is a knock out on the new air cleaner, but I will look. All messages have been helpful...please continue with any or all input.


Run it to the large vacume port on the lower front of the carb/intake area. Next get your self a inexpensive chrome oil breather cap at auotzone to match the air cleaner. This breather cap will mount into the driver side valve cover where you fill it full of oil.

 

[JTCamp]

Here's a question. I have the PCV hooked up to the PCV port on the carb coming from the pass. side. But on the driver's side I was told to hook up a hose from the valve cover to the air cleaner. Before I did this I just had it vented and I got lots of smoke out of it...after I routed it to the air cleaner no more smoke...is this not right? Thanks and sorry for jumping the thread.

John

 

[Skuzzlebutt]

[quote author=jtcamp link=board=5;threadid=17197;start=0#msg131329 date=1052343884]
Here's a question. I have the PCV hooked up to the PCV port on the carb coming from the pass. side. But on the driver's side I was told to hook up a hose from the valve cover to the air cleaner. Before I did this I just had it vented and I got lots of smoke out of it...after I routed it to the air cleaner no more smoke...is this not right? Thanks and sorry for jumping the thread.

John
[/quote]

To check if the PCV is working right pull it out of the valve cover while at idle and there should be strong vacuum hissing thru it (the valve), and the idle should drop. If not, either it is attached to the wrong port on the carb or the valve is stuck. When everything is working properlike the vent on the other valve cover should be letting clean air into the engine. Since yours was letting smoke out you're either not getting enough vacuum thru the valve OR you've got a high milage engine creating more more gases than the PCV can handle.

 

[Guest]

??? Let me get this straight...all help very appreciated.
I currently have a 73 302 V8. The drivers side valve cover has the oil filler cap that is lined straight to the bottom of the carb. The passengers side valve cover was lined to the air intake. Since replacing with a chrome air filter, what do I do with this line (air breather w/filter or line to carb and air breather on oil filler cap)?

What is correct? Pass side valve cover to carb and air breather on oil filler cap OR oil filler cap to carb and air breather on pass side valve cover?

Thanks, I hope I am not confusing.
Chad

 

[Yellow75]

Well, I'm not sure that it makes much a difference which side but.... I have the drivers side valve cover hole (is on the front of the valve cover) with the pcv valve going to the drivers side valve on the carb. My pass. side hole (rear of valve cover) has the breather in it. Runs fine for me?

Oh, and to fill it I pull the pcv valve and put the oil in there..

 

[Gordys74]

I believe you can do it either way, but since your oil filler cap is already hooked to the carb (mine is too, that was the stock set up) you can just replace the pass. side hose and fitting with a filter or drill a hole on the bottom of the new breather, put in an elbow, and connect the hose there. Just be sure the hole is on the clean air side of the air filter. Thats the way I did mine.

 

[Guest]

;D Thanks for the help. I think I will leave the set-up with the breather on the pass side and drivers side with oil filler cap going into carb.
The cap seems to need a new valve and/or the filter element in the cap replaced. Any ideas or part numbers?

 

[Yellow75]

Just go to a parts store and get a pcv valve for a 302. It should fit right in with a tree on top for your hose to the carb.

 

[BwoncoHowie]

[quote author=Chad link=board=5;threadid=17197;start=0#msg131442 date=1052364106]
??? Let me get this straight...all help very appreciated.
I currently have a 73 302 V8. The drivers side valve cover has the oil filler cap that is lined straight to the bottom of the carb. The passengers side valve cover was lined to the air intake. Since replacing with a chrome air filter, what do I do with this line (air breather w/filter or line to carb and air breather on oil filler cap)?

What is correct? Pass side valve cover to carb and air breather on oil filler cap OR oil filler cap to carb and air breather on pass side valve cover?

Thanks, I hope I am not confusing.
Chad
[/quote]

Chad,
The way the PCV works is this:
Intake manifold vacuum pulls a metered amount of crankcase gasses through the PCV valve and into the intake manifold system below the throttle plates to be burned with the air/fuel mixture.

The vent at the other end on the opposite valve cover is there to let more air into the crankcase to replace the gasses that get pulled out. The fresh air being let in needs to be clean-filtered air that is usually drawn form a clean air source within the clean air intake system for the engine.

If yours is a 73 then your PCV valve plugs right into a rubber grommet on your oil cap in the valve cover on the left (drivers) side.
Your vent tube, which is at the opposite end on the other valve cover, needs to connect to the base of the air filter housing. If you don't have a punch-out, you will need to drill it in order to install your kit, which is nothing more than a hose connection to your filter housing. On most chrome air filter housings, the clean air hose hooks up somewhere on the bottom half of the filter housing. Factory chrome filter housings like what was used on the Hipo 289, Boss 302, 427, and many others, already had that hose connection built in. In your case you will need to install your own if it’s an aftermarket housing.

BH

 

[Guest]

;D Thanks everyone for the help. I put a breather filter on one side and replaced the PCV coming out of the oil filler cap.
It eliminated the fuel rich gray smoke out of the exhaust upon start-up. Seems to run better since replace the PCV and adding the breather....think it is getting increase air flow to the engine.