Speaking of PCV..

[toocrazy2yoo]

So, I was re-clamping my pcv/catch can hoses the other day, and wondered where the air comes FROM to feed the crankcase ventilation system. This is a 1.6 Hyundai 4-banger DOHC.

My hose for the catch can comes out of the camshaft cover into a connection point molded into the rubber boot downstream of the filterbox, upstream of the throttle body junction.

Bolted onto the aluminum throttle body downstrream of the boot-hrottle body junction is a flange, and off of that is a larger diameter hose that goes to the cam cover. I know the first hose I described is pulling into the throttlebody, because I've tested it with a vac gauge.

Is the second hose the supply for the PCV? Or is there another air supply into the crankcase also? I don't see any other hoses coming off the intake or filter box or ducts that go anywhere..

Thanks!

 

[Matt_S]

Every engine has some blowby, even if very small. That's what feeds the PCV system. The PCV connection to the throttle body basically pulls a very small vaccuum on the crankcase to pull those gasses out and re-burn them so they don't pollute the air.

 

[brianl703]

Quote:

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My hose for the catch can comes out of the camshaft cover into a connection point molded into the rubber boot downstream of the filterbox, upstream of the throttle body junction.

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That sounds like the air supply for your PCV valve.

Usually air is drawn into the camshaft cover, from a point upstream of the throttle body. It's this way on every PCV system I've ever seen.

 

[Drew99GT]

Except my Corolla, which has the inlet side past the throttle body. It's weird, because the inlet hose is the smaller diameter hose as well; usually the inlet side is huge compared to the PCV side so as to induce vacuum in the smaller line so the air goes that way. I guess the PCV valve itself does that on mine.

 

[brianl703]

The PCV valve is almost always a one-way valve and one of it's functions is to prevent a backfire from getting into the crankcase.

 

[Shaman]

it sounds like the big hose you are refering to is you PCV valve hose. Is your catch can getting anything? I know that Hyundai has a very interesting setup in the newer elantras that alot of modded are confused about when it comes to sticking on a catch can. Alot of them are using two.

or maybe I am confused...

 

[BlazerLT]

Quote:

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So, I was re-clamping my pcv/catch can hoses the other day, and wondered where the air comes FROM to feed the crankcase ventilation system. This is a 1.6 Hyundai 4-banger DOHC.

My hose for the catch can comes out of the camshaft cover into a connection point molded into the rubber boot downstream of the filterbox, upstream of the throttle body junction.

Bolted onto the aluminum throttle body downstrream of the boot-hrottle body junction is a flange, and off of that is a larger diameter hose that goes to the cam cover. I know the first hose I described is pulling into the throttlebody, because I've tested it with a vac gauge.

Is the second hose the supply for the PCV? Or is there another air supply into the crankcase also? I don't see any other hoses coming off the intake or filter box or ducts that go anywhere..

Thanks!

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You have it installed on the wrong hose I think.

The hose that goes to the intake runner is what you need to install the catch can on.

Please provide some pictures.

 

[toocrazy2yoo]

I might do that. I was hoping RayH might appear on this one, he's a bit of an afficianado of Hyundai..

I'm catching a half a canful (probably 3 or 4 oz.) of goo every 1000 or 1200 miles. Someone pointed out, there's more lighter colored mud in there with the colder weather. So this is absolutely getting goo out of the stream. It's feeding, like I said, out of the can and into the rubber boot just ahead of the aluminum body the boot is bolted onto. No way the stuff is coming out of the boot. The big hose (maybe 1" O.D.) is just too short and flanged with bolts, there's no catch-canning THAT until out of warranty. Could never remove it quickly enough or disguise it. Makes me wonder though, where is the crankcase feeding FROM? Man, I hope it's filtered air, that's all I can say..

Thanks for the answers, all. I almost forgot I'd posted this..

 

[BlazerLT]

Just make sure you have the catchcan on the line with the PCV valve on it.

 

[toocrazy2yoo]

I'm not sure all of a sudden. Why would they pull off the crankcase at two points? No indication from the outside, and the owner's guide gives no clue either. But there's no doubt, this stuff would wind up entering into the rubber boot. I gotta put out the call at the Elantra club, maybe someone over there knows.

 

[BlazerLT]

They don't......

One allows fresh air into the crankcase, and the one with the PCV valve sucks the gas and sludge into the intake.

 

[Shaman]

Remember that there is alot of sucking past the TB plate no matter what, but there isn't alot that can go through the plate at idle. Therefore, the hose past the plate should be the one sucking it out. Link the EGT thread when you get it posted up.

 

[The_Jeff]

My 99 hyundai accent had a large 1" diameter hose that bypassed the throttle body. Looked like an idle speed air control bypass that was bolted on for US cars. Can picture this thing being sold the rest of world over with people just turning the throttle stop screw when they needed.

here's a pic of my setup, sorry the valve cover is off, might make it easier, might make it harder... don't have the car anymore so I can't get you a better shot...

 

[Drew99GT]

That's exactly how mine is. You can see that the fresh air line is larger in diamter than the line that holds the PCV valve. If you think about it, a smaller diameter hose with the PCV valve in it will create more vacuum through it (Bernoulli's principle) and the air will flow that way, EVEN though both lines are routed to the intake manifold.

 

[toocrazy2yoo]

On mine,the large pipe coming out of the valve cover is the one flanged to the aluminum. The smaller hose connection is the one the catch can processes. And it is catching oil..