PCV and Breather?

[FBC72]

Just curious of opinions on this. How many of ya'll run a PCV on your older small blocks, and also how about a "push in breather" on the valve cover?

[Burt4x4]

I had Two! well I started with one PCV on the drivers side and a push in breather on the other. Then I DROVE my K5 from Cali to Moab, wheeling for 3 days, then drive back. Dirve back was "different". Every now and again my rig would SMOKE OUT the entire hwy, then the smoke would stop. Well looking at the engine Oil was everywere and the smoke was from the oil landing on the headers. I assumed I blew a front main seal, adding a quart or two, every 60 miles was my paln to get home. Man the whole under side of my rig got coated in oil.
ANYWAY... we just crossed over into Cali, Barstow, HOT desert, My buddies engine broke a rocker arm stud so we were stuck.
My other buddy suggested I add a seconf PCV to the other side as my problem may not be a bad seal but "blow-by" excessive pressure building up inside. Got a T & more hose and another PCV and installed...no more oil spitting out all over my engine
So yes use one or two hahaha

[DPowers]

I run both on my 283

[snj8198]

Hey Burt are you saying you are running 2 PCV's, 1 in each valve cover and you T'd them together?

[Burt4x4]

Yup, this was my original engine. At the time I pulled it and did a compression check, one of cylinders was 90 and the rest was like 180. So the cause of my excessive crankcase pressure was abad set of rings = blow-by.
I simply cut thr PCV hose insert the T and hose to the other side and my engine quit leaking everywere. Drove it like that for 3yrs untill I pulled it and found out about the weak cylinder.

[snj8198]

interesting, makes sense.

[Firebirdjones]

All of my cars are still equipped with the PCV setup and one open breather in the other valve cover.

[cparman]

I have a PCV in all of my stuff as well. In my Blazer, the PCV in in the right valve cover. in the left valve cover I have a breather with a nipple attached to it. there is a hose that runs to the air cleaner. This way I am getting filtered air to the engine. open breathers work just fine as well, My way took longer, required more pieces, more trips to the parts store. That way I get to drive my Blazer more! haha

[68GMCCustom]

both

[FBC72]

yea, I currently have a PCV on the passenger side, as well as the oil filler hole, and a breather on the drivers side. I initially put a plug on the drivers side, and it appeared I was getting some minor "blow" from the dipstick on the drivers side. I didn't run a PCV before, but when I put the blazer back on the road here just a few weeks ago, and got the engine all tuned up, I thought the PCV was a good idea. I think I'll run it this way for a while, and see how it does.

[ETsC10]

PVC on the left and a vent leading to the air cleaner on the right.
IMHO--a working PVC is crucial to lifespan of my engines seals.

[Dusty71blazer]

Ok, can somone clarify this a little? I just have a breather on one side and an oil plug on the other side. To install a PCV system I should replace both with PCV valves, connect them together with a tee fitting and connect the branch side of the tee to the air cleaner? Doing this will provide what benefit? Does this fix or hide blowby issues, does it affect oil leaks?
Sorry in advance if this is a dumb question.

[old man jimmy]

Originally Posted by Dusty71blazer

Ok, can somone clarify this a little? I just have a breather on one side and an oil plug on the other side. To install a PCV system I should replace both with PCV valves, connect them together with a tee fitting and connect the branch side of the tee to the air cleaner? Doing this will provide what benefit? Does this fix or hide blowby issues, does it affect oil leaks?
Sorry in advance if this is a dumb question.

Not to the breather. You have to hook it to vacuum. It sounds like everyone has their own opinoins on the pcv valve. But the idea is the same. To vent the engine. The pcv was one of the first attemps at smog control. It's really nothing more than a check valve. One is ok, two are ok. A dozen are ok. Or none is ok, as long as you have an unclogged vent for the engine.

[Longblock]

Originally Posted by old man jimmy

Not to the breather. You have to hook it to vacuum. It sounds like everyone has their own opinoins on the pcv valve. But the idea is the same. To vent the engine. The pcv was one of the first attemps at smog control. It's really nothing more than a check valve. One is ok, two are ok. A dozen are ok. Or none is ok, as long as you have an unclogged vent for the engine.

I Agree.....

[Dusty71blazer]

Originally Posted by old man jimmy

Not to the breather. You have to hook it to vacuum. It sounds like everyone has their own opinoins on the pcv valve. But the idea is the same. To vent the engine. The pcv was one of the first attemps at smog control. It's really nothing more than a check valve. One is ok, two are ok. A dozen are ok. Or none is ok, as long as you have an unclogged vent for the engine.

Thank you!

[Longhorn Man]

Your crank case is filled with misted oil particles, fuel vapors, and residude from the conbustion that gets by your rings. All this is normal. When all this mixes together, along with water vapor from the humidity in the air, it becomes acidic, and contaminates your oil.
The PCV sucks all that crap out of the air that is trapped in the crankcase, and feeds it into the incoming air/fuel that is headed to the comustion chaimber for burning.
For simplicity, we'll compair the crankcase with your kitchen after you burned your dinner real good. I mean REAL good, thick smoke, hardly see across the room, let alone inhale.
1. You can open one window, and that'll let some air out.
2. Or you can open 2 windows... that's be better.
3. Or, you can open both windows, and place a window fan in one aimed out, to suck all the smoke out, while clean, fresh air comes in the other window on the other side of the room.

#1 is your engine with one breather.
#2 is your engine with 2 breathers.
#3 is one breather, and a PCV valve.

While this IS a polution control device, (and reqired federally in all 69 and later trucks, 64 and later in cars) it is one that has no performance killing drawbacks, and HELPS your engine last longer and run cleaner. And by cleaner, i don't mean smog, I mean crap in the oil, getting ground into the bearings and cylinder walls, causing poor oil pressure and less performance.

The way the factory did it on these trucks, was an oil fill, a PCV, ans a fresh air tube that was plumbed into a steel collar that went under the air filter. This is better than just a breather, this way, the fresh air being sucked into the engine, has been filtered by the large airfilter that is on top of the carb.

Installling 2 doesn't do anything good. If you have 2 on the same valve cover, with the fresh air inlet (breather or tube to the air filter) then it may do more than just one. If you install one PCV valve on each valve cover, with no vent, you can suck a gasket into the engine. Usually the intake end gaskets. If you do a PCV on each cover, and one vent, then the air inside that is supposed to flow from one side to the other gets disrupted. If you seal the engine off, no PCV, no vent, no road draft tube (pre PCV system) then you will end up building up positive pressure inside the crank case and spitting gaskets out.

Some remove them for aesthetic reasons, personally, I don't see them as being all that ugly. you can get aluminum ones from places like Jeggs or summit, and then steel braided hose if it pleases your eyes a little more, but in my personal opinion, it is a must have for anything but an all out show truck that rides in a trailer to get to the show.

[Dusty71blazer]

Thanks longhorn, great info!

[Burt4x4]

I totaly agree LHM, in my case, running two PCVs with exsessive blow by, then add your theory, my "bad" rings on the one cylender, turned it into a breather sorta all I know is my engine quit pissin oil out of the front crank seal once I added a second PCV = bandade
On my current engine, 454, I run a breather on the pass side and PCV on driver side

[-Greg72]

Originally Posted by Burt4x4

I had Two! well I started with one PCV on the drivers side and a push in breather on the other. Then I DROVE my K5 from Cali to Moab, wheeling for 3 days, then drive back. Dirve back was "different". Every now and again my rig would SMOKE OUT the entire hwy, then the smoke would stop. Well looking at the engine Oil was everywere and the smoke was from the oil landing on the headers. I assumed I blew a front main seal, adding a quart or two, every 60 miles was my paln to get home. Man the whole under side of my rig got coated in oil.
ANYWAY... we just crossed over into Cali, Barstow, HOT desert, My buddies engine broke a rocker arm stud so we were stuck.
My other buddy suggested I add a seconf PCV to the other side as my problem may not be a bad seal but "blow-by" excessive pressure building up inside. Got a T & more hose and another PCV and installed...no more oil spitting out all over my engine
So yes use one or two hahaha

Good times.....


Burt's Awesome Single-PCV setup...



Broken Rocker Stud Repair in Barstow, CA...



Don't forget stopping to let me get fuel every 160 miles!!!






-G

[Dusty71blazer]

Originally Posted by Burt4x4

On my current engine, 454, I run a breather on the pass side and PCV on driver side

Does this matter?
Would it make a difference what side has the breather & what side has the PCV?

[Burt4x4]

hahahah Awesome Greg!! What a great trip!

Dusty ~ I have no clue if it matters wich side you use. Positive Crank Ventilation is a good thing!

[Longhorn Man]

on an engine that does not have excesive blow by, it won't matter which one is where, as long as one is on one side, and the other on the oposite side.