anyone ever use a crankcase vent filter

[spoman]

I've been an issue where oil gets into the air intake housing. I was thinking of replacing the tube that goes frlm the valve cover to the air intake with one of these: http://pages.ebay.com/motors/link/?n...d=170899334994

Anybody have any experience with these? I'm worried about oil spraying all over the engine.

[gestiva]

I got one for $9 at Orielly's, But took it off after advice from someone who said I had to remove the PCV and hose???? Still got it, and running stock intake, and saw no decrease/increase in my preformance...
Unsure if on a "stock" engine it is worth it, other than looking better that stock intake?.... (on a BP engine)

[bravekozak]

Yes, I used one when I did my Weber conversion. No oil on the valve cover.
However, I have my PCV vent hooked up to my air cleaner now that I have changed carbs again.

[rmoltis]

The blowby vapors that end up in an engine's crankcase contain moisture as well as combustion byproducts and unburned fuel vapors. The crankcase is sealed to prevent the escape of these gases into the atmosphere, but the vapors must be removed to prevent oil contamination that leads to sludge formation. The positive crankcase ventilation (PCV) system siphons these vapors from the crankcase and routes them into the intake manifold so they can be reburned in the engine.

The PCV valve is a spring-loaded valve with a specific orifice size designed to restrict the amount of air that's siphoned from the crankcase into the intake manifold. This is necessary because air drawn through the valve from the crankcase has a leaning effect on the fuel mixture much the same as a vacuum leak. So air flow through the valve must be controlled within certain limits. At idle, air flow is reduced because little blowby is produced. When the engine is cruising and vacuum is high, airflow through the PCV valve is at a maximum to purge the blowby vapors from the crankcase.

It's important to note that PCV valves are sized for specific engine applications. The wrong PCV valve for an application can flow too much or too little air causing driveability problems. Varnish deposits can clog the valve, so replacement for preventative maintenance is recommended (every 50,000 miles usually).

Personally I wouldn't remove my pcv valve because of the above listed reasons. I'd like to keep the inside of my engine clean, and my oil free of moisture and gas blowby so it lasts longer between oil changes. Without vacuum drawing out the vapors they would just recirculate mostly and eventually settle in the oil. While small amounts escape. And also the filter won't filter the unburnt fuel it would just pass by into the atmosphere causing more pollution.

If anything you could take that hose and remount it to your intake tract farther up closer to the manifold so your air filter box stays clean and it would still be able to do its job properly.

[Aaronbrook37]

http://www.fordfestiva.com/forums/showthread.php?30569-Aaron-s-Festiva-Build-Thread&p=566782&viewfull=1#post566782

Here's a link to my quick DIY catch can. The stainless steel scrubbers force the oil vapors out of the air and into the bottom of the thermos, reducing the oil secreted from the valve cover and getting through the PCV by a considerable amount. Built it for $20 give or take. Killed my smoke at startup and reduced smoke during driving low speed considerably.

[georgeb]

My patched '93 is seeping oil out of the oil cap. I suspect blowby. I might have to rig up some kind of pressure relief. I'm trying to milk a few more miles out of this 275K-mile engine.

[Aaronbrook37]

My patched '93 is seeping oil out of the oil cap. I suspect blowby. I might have to rig up some kind of pressure relief. I'm trying to milk a few more miles out of this 275K-mile engine.

A can of sea-foam might get you a bit of relief... unsure though. Might be worth readying that new head and block sooner than you think if you're sick of buying oil jugs!

[bravekozak]

This filter is to allow air into the top of the valve cover. It gets sucked out through the PCV valve. It really doesn't matter if the air enters from the air cleaner through a small filter or through that mini air filter in post #1. Besides, there is an oil baffle underneath that vent barb on the valve cover.

[rmoltis]

You know what would great for this idea/application. You guys here with air compressors or that work in construction with air tools. They tend to have the oil/ air seperators. They spin the charged air through the chamber and the heavy particles sink to the bottom of the chamber while the air remains seperate to flow back out. This would be a good way to let the vapors flow through back to the engine while removing the sludge and heavy particles to be drained at a later time. I know its just an idea but it seems solid.

[rmoltis]

Not to mention they probably make oil/air seperators as an aftermarket option for cars. Just run it inline between the pcv valve and the intake tract. Or whatever tube you are referring to.

[Aaronbrook37]

Not to mention they probably make oil/air seperators as an aftermarket option for cars. Just run it inline between the pcv valve and the intake tract.

This is a popular option in the Honda community as do-it-yourself catch cans. Husky makes them. Here's an example: http://www.svtperformance.com/forums...-write-up.html

[rmoltis]

That's perfect. It's exactly what I was thinking. I'm wondering if your oil level would get low being that the oil wouldn't recirculate back into the engine. This is a mod I think I want to do in the future. I don't like having to clean the intake manifold every time and again from buildup. This would be a great solution.

[PhoenixSHO]

Plenny of catch cans on ebay , look them up , its cheap and universal.

[koRnhead]

If your worried that your oil level will go down because of a catch can.......
You are aware that oil in your intake tract doesnt circulate back into the pan right??

[bravekozak]

Has anyone taken off the baffle in their valve cover to see the crud that has built up over the years? It's tough to get those screws out. You need to rap the screwdriver with a hammer as you turn. I would recommend loctite when reinstalling them. You don't ever want a screw to come loose and fall into your valvetrain.
Sometimes the crankcase vapors can hardly get through, due to the buildup at the six gates between the vent tube and the pcv valve.