Crankcase ventilation

[BelvedereSatellite1966]

Hi!

Bought a Satellite 1966 with a 383.
On the engine there is valve covers from mopar performance.
On the drivers side there is a breather attached, but the other valve cover there are no ventilation attached.
When the engine is warm there are coming a little bit of smoke from the breather, when the hood is closed you cant see the smoke coming out to give you an idea how much smoke coming out.
So it's not much smoke coming out.
The oil looks find, no signs of water in the oil.

I've noticed that my vacuum reading is shaking and moving around 2 in/hg on idle, and what i read i may have some sticky valves.
I cleaned my breather as it was a tip from someone when you have unsteady vacuum-reading at idle, and it struck me that it's wierd that i may have sticky valves as the engine was teard down and has only been running about 15 hours since that(teardown by prevoius owner).

I've tried to read and look at pictures on other engines with only a breather on one side of the engine, but i'm starting to feel worried that this setup is bad as i've only seen people running PVC and breather or breather and breather.

So what should i do?
I have a Edelbrock performer rpm and the factory vacuum-port on this is now connected to the brake booster and the vaccum-port on the carburator is plugged permanent, but i should be able to drill it out again.

So i wonder if i just remove the oil fill cap on the passenger side and replace with another breather, or buy a PCV and plug to manifold?
After that i thinking of try some seafoam(or whatever i can find here in Sweden) and see if i can get a better vaccum reading.

Any thoughts on this?

Thank you in advance, and excuse my spelling and grammar.

Br.
Viktor

 

[1967coronet]

Some run 2 breathers {one on each side} and get away with it.
Myself I like the PCV valve hooked to the intake under the carb and then a breather on the other side to let air in. gets rid of most of the pressure in the crank case and helps keep the gaskets ect sealed up.
Make sure to get a PCV valve that is correct for your engine if you go that route.

 

[Ranger16]

A breather on one side is like opening one window and expecting ventilation after burning dinner. You need to open one on the other side. Like Coronet said, the breather cap/oil fill cap is the intake side of the PCV system. You need a suction side with a PCV valve on the other side routed to the large vacuum port on the bottom of your Edelbrock carb.

Here is a diagram. The picture of mine is below. Click on it for a larger view. I think you can make it out OK.The only difference is that mine is not drawing fresh air through the factory air filter housing.

 

[BelvedereSatellite1966]

Thank you both for your replies!

How much loss in manifold-vacuum do you look at when installing pcv?
Running a bigger cam with 11-12 in/hg in manifold today.
And when looking for the correct PCV, what is the specs to look at so i don't get it wrong?

Br.
Viktor

 

[Jcharger]

I know a number of people run without PCV valves. I decided to run the PCV valve to pull the fumes out of the crankcase and oil.

Here are two things to consider:

• If you have low vacuum (10-12 inches), you may need to use a PCV valve other than stock to have it work properly. I do not know how to choose the right one, but am using a 2057 because I read that some others were using that.
• If there is a lot of oil and exhaust coming from my crankcase, it can foul the plugs and lead to detonation. Some use a catch can, and some alternatively send the ventilation to the exhaust. [For the time being, I am trying to run the PCV after a stock breather cap (it is a kluge). I have not yet checked the plugs, but will be able to tell in the Fall whether there was any difference.]

Good luck with your project.

PS. Did you mistakenly type that you have 2 inches of Hg rather than 12 in the first post?

 

[BelvedereSatellite1966]

What i meant was that my vacuum-reading is pending with 2 in/Hg, it floats between 11-13 or 10-12 Hg.
What i've read it may be because sticky valves, timing not properly set, or lean/rich mixture.
I now have a Holley 850 DP(I know it's BIG for my application, don't know why previous owner went with it) and i'm on my way to install a AFR-meter to set mixture correct and then look at timing.
When i checked 13 degrees initial at idle, but i think my advance starts to early and the reading i get on idle is under advance.
I have about 26 degrees total timing and as the bushing should give me 18 degrees advance its not correct, 13 initial plus 18 advance should be 31.

When i have this under control i will take a look at my ventilation, if i still have problem with vacuum-reading i think i need to remove my valve covers and check that the valves are not stuck.
I'm leaning on just install another breather because of laziness and fear of loosing vacuum as it's already low.
I don't know what loosing more vacuum does performance-wise if installing PCV, maybe someone can fill that in for me.

Thank you everybody for the answers i got already!

 

[Ranger16]

I don't think having a properly operating PCV system will hurt performance.

I saw a very good article on why you should run a PCV system about a year ago, but I've searched and searched and cannot find it. Should have bookmarked it.

 

[4spEd]

I know a number of people run without PCV valves. I decided to run the PCV valve to pull the fumes out of the crankcase and oil.

Here are two things to consider:

• If you have low vacuum (10-12 inches), you may need to use a PCV valve other than stock to have it work properly. I do not know how to choose the right one, but am using a 2057 because I read that some others were using that.
• If there is a lot of oil and exhaust coming from my crankcase, it can foul the plugs and lead to detonation. Some use a catch can, and some alternatively send the ventilation to the exhaust. [For the time being, I am trying to run the PCV after a stock breather cap (it is a kluge). I have not yet checked the plugs, but will be able to tell in the Fall whether there was any difference.]

Good luck with your project.

PS. Did you mistakenly type that you have 2 inches of Hg rather than 12 in the first post?

Quick flow has a good air oil seperator. I put it on mine cause I didn't like seeing smoke when I got on it.

 

[coloradodave]

You can run open breathers on both valve covers but you will get some oil vapor condensing on top of the motor which needs to continually be wiped off if you take pride in the looks of your motor. I would recommend installing a PCV valve in the passenger side valve cover after pulling the cover and making sure that there is a baffle in place to stop the valve from pulling oil, instead of vapor. As Ranger 16 said, a properly installed and sized valve will NOT affect your horsepower or vary your vacuum readings. You can order a stock PCV valve for the cubic inch and year of your motor from rockauto.com or any auto parts store. I would also check that the driver's side valve cover has a baffle in place under the breather, just to insure oil splash doesn't weep up into the breather and leak out onto the cover. The 850 Holley has a 3/8" tube on the bottom rear that will accept a 3/8" PCV hose. Hopefully you can modify it to work if someone sealed it. If not, you can always use a brass 'T' at the power brake fitting. Manifold vacuum is manifold vacuum...Good luck.

 

[747mopar]

^^^^^^^ My motor is set up just as Dave has described, PVC valve to the bottom 3/8" carb fitting with a breather on the opposing side. No oil leaks, no oil spill, no problems.

 

[BelvedereSatellite1966]

Thank you all very much for the information.
I will install AFR-meter today and do a little bit of tuning, after that i go further with my ventilation solution.

I will post a answer and maybe some pictures how the installation and my idle-vacuum problem resulted, if i don't forget .

Thank you again!

 

[watermelon]

good info in here

i wanted some type of filter in between the pcv valve and my MSD Atomic throttle body because there are a few sensors in there that i dont want to get gummed up

air/oil separators look like the ticket



Ranger16, are you running iron heads under those MP Cast valve covers? If so, what type of gasket you have on those? (Do those MP v/c have baffles?)

 

[Ranger16]

Yes, I'm running factory heads.
I have the rubberized gaskets, from Felpro I believe. I had to use RTV to seal the right side.
Yes, both sides have baffles.

 

[bigmanjbmopar]

I find that one open breather on one side and a combo PVC and breather on the other work really well, catches the oil in the filtered breather so only fumes get back into the manifold to re burn and keeps the pressure out of the motor. It twist in the oil cap spot so no having to cut new holes.

http://www.ebay.com/itm/like/162081...Covers+Small&vectorid=229466&tc=US&rmvSB=true

 

[1967coronet]

I find that one open breather on one side and a combo PVC and breather on the other work really well, catches the oil in the filtered breather so only fumes get back into the manifold to re burn and keeps the pressure out of the motor. It twist in the oil cap spot so no having to cut new holes.

That's a good idea, nice set up.

http://www.ebay.com/itm/like/162081...Covers+Small&vectorid=229466&tc=US&rmvSB=true

 

[khryslerkid]

I need to make or buy a baffle for the Cal Customs that I have.

Or would you need a baffle under those breather/pcv mentioned?

 

[coloradodave]

The baffles are a good idea. Easy to make.

 

[watermelon]

khryslerkid,

i think you would need baffles in the covers to prevent oil from being pulled into vaccum rather than just the vapors like coloradodave mentions.

my factory stamped metal ones have baffles on both sides. my covers are a bit warped so i have some leaks; tried a nice cometik gasket n thin rtv coat but didnt fix

pulling the covers off again and gonna see if i could work them flat again

 

[Ron H]

Wow! These are some pretty motors pictured....I'm totally envious and hope I can get to this level with my '63 Fury! Hope to do the rebuild over the winter...I'm likely to be asking for advice...Ron H.

 

[bigmanjbmopar]

Mopar performance covers should have the baffles on both oil holes already if you use the twist ins then you wouldn't need to drill out the other spot for a push in type like mine on the drivers side, I just had a preference of wanting to use the front oil hole for refilling vs pulling a breather out to oil just me lots of people do it that way. Isn't it nascar that pipes two breathers together from each side and then puts it back in the motor?