What's under the CCV puck?

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

I have read every thread I could find about the puck, but can't find a discussion about what the puck connects to...

With my puck removed, air passes through it easily. With it installed, no air... it seems there may be a check valve or something inside the valve cover - I want to be sure that's expected/normal, and there isn't something clogged or damage inside.

Thanks!

flash7210 · **Posted:** Mon Dec 19, 2016 4:05 pm

There are two big holes in top of the valve cover. The ccv puck sits on top of those hole.
Inside the puck is a check valve. Its just a spring and rubber flap.
Under normal conditions the spring holds the flap open.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

I think I didn't write clearly.

I understand the puck itself, but what's going on in the head? I can blow from/to any two ports on the puck when it is removed, but when the puck is installed on the head I cannot blow or suck through the puck... something in the head prevents air flow at all. I'm hoping that's by design, but if it's not, it's obviously a big problem!

flash7210 · **Posted:** Mon Dec 19, 2016 5:08 pm

The puck is the only vent on the engine.
Blowby from combustion (crankcase gasses) leave the engine through the ccv.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

Yes, I understand that.

I am trying to determine whether the puck is an actual vent (an open passageway) or whether something inside the head acts as a valve or pump or other restriction. I have never in my life seen an engine where you can't suck through the CCV when it's installed, but on the CRD I can't. There is some sort of restriction inside the head, so that when the puck is installed, I can no longer blow or suck through it. If that's normal, great, but if not an obstructed CCV system is obviously a huge problem.

GordnadoCRD · **Posted:** Mon Dec 19, 2016 5:49 pm

There should be nothing inside the head cover to prevent your breathing. Are you positive there is no blockage or kinking of your hose?

flash7210 · **Posted:** Mon Dec 19, 2016 6:06 pm

The only vent on the engine is the CCV.
There is nothing to breathe through except past the piston rings.
If you can't suck or blow air past the rings, that's a good thing.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

flash7210 wrote:

The only vent on the engine is the CCV.
There is nothing to breathe through except past the piston rings.
If you can't suck or blow air past the rings, that's a good thing.

That can't be true - there have to be oil drains from the head all the way through to the sump. Even still, I should be able to pull some air out of the head with my lungs. This is like breathing into a tiny bottle, no air goes in or out when the puck is installed.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

GordnadoCRD wrote:

There should be nothing inside the head cover to prevent your breathing. Are you positive there is no blockage or kinking of your hose?

Yes. I am using some heater hose attached to the output of puck. And, like I said, I can pass air easily through the puck when it is removed, through the hose. Once it is installed, no air goes in or out.

I am completely baffled by this.

flash7210 · **Posted:** Mon Dec 19, 2016 6:24 pm

And just like a bottle, it has only one opening.

If there was another opening, there would be a filter on it. You don't want dirty unfiltered air going into the crankcase.

Now, your old ford/Chevy gasoline V-8's were entirely different.
On the end of one valve cover was the PCV valve. On the other valve cover was a filtered breather cap.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

flash7210 wrote:

And just like a bottle, it has only one opening.

If there was another opening, there would be a filter on it. You don't want dirty unfiltered air going into the crankcase.

Now, your old ford/Chevy gasoline V-8's were entirely different.
On the end of one valve cover was the PCV valve. On the other valve cover was a filtered breather cap.

I understand what you're saying, but I am not comparing to some old car, I'm comparing to all the myriad of recent cars I own and work on. There have to be oil drains from the head to the sump, and there has to be more air in there than I can suck out with my lungs and more space than I could fill with one deep breath. There just has to be. Beyond that, it's highly unlikely the oil dipstick has a perfect seal, so I should be able to suck air from the dipstick, to the sump, through the drains, into the head. And I can't. I should have tried removing the oil dipstick just to prove a point, but didn't... I will do that later on. In the meantime -

I built this contraption. I'd originally intended to use the Mityvac, but it couldn't evacuate the heater hose in a reasonable period of time, so instead some silicone hose and an AC evacuation pump -

It will suck down to 20 inches (the pump's limit) almost instantly and just stay there -

Here is that scenario in action:

https://youtu.be/gRWcmudzcTs

flash7210 · **Posted:** Mon Dec 19, 2016 7:39 pm

Yes, there are oil drains between the head and block.

One, you remove the dipstick, remove the oil cap, or disconnect the vacuum line from the vacuum pump you should be able to blow/suck through the ccv.

Edit.
Pulling too much vacuum throught the ccv will cause the check valve to close.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

flash7210 wrote:

Yes, there are oil drains between the head and block.

One, you remove the dipstick, remove the oil cap, or disconnect the vacuum line from the vacuum pump you should be able to blow/suck through the ccv.

Edit.
Pulling too much vacuum throught the ccv will cause the check valve to close.

My lungs should not be able to generate more vacuum than the intake under any conditions... I'll redo this with the dipstick removed. Who knows, the CRD could have the best dipstick seal in the world.

GordnadoCRD · **Posted:** Mon Dec 19, 2016 8:29 pm

The dipstick, or the oil filler cap. Either will allow air in to replace the air you are attempting to move.
I like that contraption though. Holding a vacuum like that should remove all water and fuel contamination from your oil, in the same manner as removing the moisture from a AC system.

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

It works remarkably well - that's the upside.

I will remove the dipstick in a bit and see what happens... I'm hoping free air flow, but I'm not even a little confident that is what's going to happen.

WWDiesel · **Posted:** Mon Dec 19, 2016 9:45 pm

Do not forget, the vacuum pump discharges into the engine internally and contributes into whatever gases or vapors that are being discharged or removed through the CCV...

GordnadoCRD · **Posted:** Mon Dec 19, 2016 10:03 pm

I sure hope he's not sucking on his hose with the engine running! :dizzy:

thesameguy · **Joined:** Sat Oct 01, 2016 8:24 pm **Posts:** 652

I do when it's time to party!

Removing the dipstick resulted in a slight loss of vacuum, but not zero. It was too dark & too cold to continue, but I will look at it when I can - hopefully there is just some small, apparent obstruction.

Bushman5 · **Joined:** Sat Jul 11, 2015 11:05 am **Posts:** 278

can someone show me WHERE the vacuum pump discharges? Is it possible to mod it so it discharges EXTERNALLY?

Jsamps1345 · **Posted:** Wed Dec 21, 2016 9:27 am

The vacuum pump is inside of the front of the block just like the oil pump is, i know there is a picture of it mounted somewhere just cant find it. It discharges thru the hole in the block. I don't see how you can make it discharge externally unless you make an idler gear/insert to replace the vacuum pump and use and external pump of some sort.

Edit: Block is upside down in this picture FYI. The vacuum pump is the one on the left (labeled Bosch) and the oil pump is on the right (labelled VM)

http://i650.photobucket.com/albums/uu22 ... CF1792.jpg - Credit is due, not my pic

What's under the CCV puck?

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