Oil Coming Out Of Oil Breathers Help

I am getting oil out of the oil breathers on top of the valve covers. They are located towards the front of the engine near the intake on both passenger and driver's side. The valve covers have baffles in them.

Specs: 1969 Dodge Charger, 540 cui Hemi, Megablock, 4.375 bore x 4.5 stroke, Internal pickup for oiling, Miloden oil pan with windage tray, Indy 426-1 Aluminum heads, Solid roller cam, Valve lift .61 intake and exhaust, Indy cast aluminum valve covers, Open oil breathers with baffles, Fresh build, maybe 2,000 miles on it. Some track time. Block was worked, gone through by my machinist, and final torque honed. Rings were file fit according to the instructions.

I haven't done a compression test or leak down test to know if it is blow-by. I was wondering if there was anything else I should check (consider) while I'm at it?

I did not put in the oil restrictors in the heads because I had read horror stories about not enough oil to the top end on Hemis. I was thinking that it was on the safer side to have more oil than less? Should I put them in?

Do not put oil return restrictor in your heads
Do you oil the rocker arms full time with your roller cam?
How big are the baffles under your breather caps?

When did this start? What change (if any) was done before that?

That is a big engine so it will have a lot of blowby and that long stroke will stir up the oil in the pan. So no surprise that you're having oil blow out the breathers.

One thing to try is high quality breathers such as the ones that Peterson makes. They screw into a #12 bung so you might need to weld bungs to your valve covers. The other thing to try is to put the breathers on a remote tank. On the dyno I use a two quart Moroso tank with a breather and then run a line from each valve cover. That setup never leaks a drop and it doesn't blow out any oil. I've used the same type of setup in a car by mounting the breather tank up next to the radiator. I'll attach a couple of pictures.

If it was OK, and then it was not, something has changed in the engine. Leak it would be the first thing to do.

Just went through this on my 470 BB in my Dart and it was hazing my windshield while testing a carb under a hard load and it turns out a vacuum line to my pcv valve was leaking and sucking air causing ring flutter..........replace line no more oil and I removed and cleaned the K&N breather and all's well now...........

An open breather will always steam and have a little oil in it. I was thinking of just tying mine together with a piece of surgical tubing with a slot cut in the top. Like you would on carb bowl vents. I've seen some breathers set up with aluminum tubing arching up in front of the air cleaner with one or two breathers at the top of the arch. Ford??? You could also set up a PVC system or a vacuum pump. Andy's breather tank works but don't go too small with the tank. Guys used to run those evac systems to the headers. I personally never liked those or tried using them.

I like that set up although a bit large as far as packaging.........

Have you pulled the covers off yet to see if
the baffles have plenty of clearance.. if they
get pushed partly closed from the rockers then
you will build pressure in the covers

had this happen once, the breather was actually the problem. Where the pinch the seem together, eventually started undo'ing itself and leaking oil all over the covers.

I think you did the right thing by not restricting oil to the heads. I usually groove the #4 cam journal to get more oil to the heads on a street motor with stiff roller cam springs. I've smoked too many rockers and push rods to not.

As for the blowby, I agree with Andy, this motor is going to have some. Work on better baffles.

GOod luck!
Joel

I see both Andy and now Joel comment on the size of the engine "it's going to have blow by". So is a 4.375 x 4.5 Hemi going to use oil due to it's size? See my post earlier on my engine, same size, and oil consumption. Oddly enough I have no blow by, installed a trap in PVC line to check and it never collected oil?

Nothing has changed with the motor. I think that it was always doing this, I just never noticed. I kept thinking it was the valve cover gaskets. I think eventually the breathers got too saturated with oil and it became real noticeable. It always did smoke a little. Was very annoying. It would come and go. Probably just depended on how hard I pushed it. Didn't pay attention though.

This last time it was pretty bad though. It smoked all the way down the freeway. I felt bad for anybody that was behind me. I didn't push it hard at all. Just cruising with my wife and son. That was on last Friday. The motor did seem a little sluggish than usual while this was happening. I did get on it a little to try and clear her out. That did help. The motor seem to come back to life and the smoke went to an instant minimum. Was still a little smoky but not anywhere near what it was. I took it back home and opened the hood to see that both valve covers had an oil stream coming from the oil breathers.

OK, so I was thinking correctly in not putting in the oil restrictors. I oil the top end by the timed #4 cam bearing. I have had the valve covers off a couple of times and the rockers seem to be getting enough oil. The baffles were put on by Indy. They drilled and mounted them for me. They are pretty stiff and seem far enough away. The grommet does not touch the baffle when installed. The breather is a K&N push type breather 1.25 opening.

Andy, I will investigate that setup further. That looks like that is the setup I will need. By the way, I have your aluminum timing chain cover on this motor. Love it!!

Is it a good idea to still do the compression test and leak down test or just focus on getting a better setup for the oil breathers?

I have never tried to post a picture so if someone could tell me how to do that, I would appreciate that.

Oh, wait - I already posted 10,000 words on this, and no one read it.
My bad.

There's likely nothing wrong w/ the motor, just the nature of the beast. That big motor is gonna make a lot of crankcase pressure and there's gonna be a lot of oil mist in there.
I know, my 572" hemi did it the first time I drove it w/ just two open element breathers on the valve covers.
I added baffles and got the Mr. Gasket breathers that sit up above the covers w/ tubes, then added steel wool inside the tubes...which helped a lot, but still ended up leaking oil if you drove it hard.
I eventually put a vacuum pump on the motor, which cured it.
Having said that, I don't think you need a pump to fix it.

My other car is a wedge, but I use a pair of -10 lines from each valve cover that "tee" into a breather tank mounted beside the radiator. This setup works great, no leaks, and much less expensive than a vacuum pump. See pic...

If its smoking that bad you most likely have
a broken ring.. OR the intake is sucking in
oil that would be where I looked

Here is a road race setup from a car that I once worked on. It was heavy and ugly but it worked. We eventually changed it over to dual #12 lines that went to a tank and that worked just as well but took up less space.

The NASCAR guys used to run systems like this before they went to dry sump. With a 8000 rpm engine running 500 miles and pulling 1 g in the corners you need more than just breathers on the valve covers.

I will do a compression test and leak down test for peace of mind.

I don't have the oil breathers plumbed back to the intake. They are just open to atmosphere. There was a lot of oil on top of the valve covers that leaked onto the headers causing the smoke. The oil breathers themselves were soaked with oil.

Here is another setup from a real NASCAR car that a buddy of mine owns. I think this is an early 70's car. Same type of deal with a crossover tube that has breathers mounted on it. That was the standard setup back in the day.

The large diameter of the systems on those NASCAR
will drop the air velocity and IF your pulling
oil out of the breathers it will help a ton.. it
really slows the air down

Do you have and use a stock type PCV system? If not that may help you when cruising at part throttle
I ended up having to use two PCV valves with two large breather caps, one on each side of both valve covers my old 518 C.I. pump gas street motor to help stop the oil breather caps from dripping oil out of them. I would wash them out in cleaning solvent every two or three months to help keep them from getting oil soak
Let us know what you do, we don't call them elephant motors Hemi roids for nothing
They can be a true pain in the rear

I do not have a stock type PCV system. I am hiding the big boy under the stock hood so air cleaner options are neel to none. I am using two Holley 600's in line on top of a stage V dual plane intake.

I am at least a little more relaxed with understanding that this is more of a common problem than I first had anticipated. I honestly thought a tear down was in my near future. It still may be but this is promising that it is possibly not a bad ring. I have already been looking at some oil catch can options from Summit Racing. I will definitely keep you posted. I would love to show some pictures but I need help with how to post them?

Edit: I think I figured out how to add pictures. I apologize if it comes in to big. If it does, next I will work on how to make it smaller.

Posting pics is impossible if you don't know how but easy once you know. You need pictures on your hard drive that have been resized. If you don't know how to resize pictures then you'll need to download a resizing tool.

Once you have resized pictures on your hard drive you just hit the switch to full reply screen button and then select the picture from your hard drive and add it to the thread.

Resizing is the trick.......

I'd dump those air filters also cos they rob lots o power and have see it first hand.............

On a Hemi you can’t have the breather directly over the intake valve spring. Relocate the breathers closer to the spark plugs and Install a baffle under it and it should stop. There are a lot of pictures on our FB page of Hemis with breathers for proper location.

The 500" motor in my 69 Dart had a 700 lift roller and always tried to push every gasket out, probably needed a vacuum pump but I did run the evac hoses to the collectors and helped a lot.


The 500" motor in my street car only has a small 557 lift solid cam and was fine for a couple years with just small breathers on the valve covers but once the breathers became oil soaked they started leaking. I put some baffled breather stands on the covers and it seems to be fine now.


Running hoses from the covers to an aluminum tank seems to be the hot setup as some of these guys have already mentioned.

Browsed through a ton of crap here over the years..... sorry I missed it

So how much oil is your engine using? I would love to know. My setup is very similar, (bore/stroke) I use a factory PVC and an open breather on the opposite valve cover. I have ZERO blow by even with the 4.5" crank. But, with clean plugs, no leakes, I use a quart in 250 miles.
What about you?

I have been extremely busy this week so I hadn't had a chance to get to it. I honestly don't know off hand? When I get to it on Saturday, I will check how far it is down. I have the speedometer disconnected so I won't know the mileage though. I am interested in what the plugs look like.

I would think you might benefit from a oil separator type breather.




Joe

We put a PVC on the pass side of my bro's 517 Hemi & he has had no oil issues for 5-6 yrs. Also, a pic of Chuck's Best Machine Hemi breather locations.

Following this thread because I'm wondering if I should be doing something different than using 2 basic Mr. Gasket breathers (the ones that look like they should be connected to a header pan-evac fitting) on my no-baffle Indy cast valve covers.

I'm following this also. I'm running the evac system in headers. Not have any problems just wondering if something else would be better

Having to do anything other than upload the pic is utterly exhausting and that is an understatement at best. Time for Moparts to get out of the late 90's and realize that smart phones, tablets and other such devices is how pictures are posted. Time to start catering to the next generation of Mopar gearheads instead of catering to the 3 dozen guys with 15 year old desktops in there basement or garage

I did a compression test and I think that it turned out pretty good.

Results:
1) 185
2) 185
3) 190
4) 180
5) 185
6) 180
7) 185
8) 170

It looks like all I will have to do is add an oil catch can. I have been looking at them and there a lot out there. Any suggestions on what type of setup I should use?

Something is going on for you to have that much blow by. I have the same bore/stroke combination and I have no blow by, none. I am running stock valve covers with a stock push on breather on the driver side and a pvc valve in the passenger side. Can you use stock valve covers?

I can not use stock valve covers. These are Indy 426-1 Legend Aluminum Heads. Stock valve covers won't work. On a side note, what carburetors are you using?

Two 750 cfm Holly's. Air horn milled off, no choke.