Moparts

Oil blowing out of breather

Posted By: frank

Oil blowing out of breather - 11/27/14 11:20 PM

Oil is blowing out the breather located in the left valve cover. Its enough to puddle on the floor after I drive the car for about 5 or more miles. What is causing this and how do I fix it?
Posted By: moparpollack

Re: Oil blowing out of breather - 11/27/14 11:25 PM

Do you have a pcv valve on the car?

Are the baffles in the valve covers?
Posted By: Cab_Burge

Re: Oil blowing out of breather - 11/27/14 11:40 PM

Quote:

Oil is blowing out the breather located in the left valve cover. Its enough to puddle on the floor after I drive the car for about 5 or more miles. What is causing this and how do I fix it?


Crankcase pressure is the only reason that oil will be blown out of the breather caps Two possible causes, possibly a combination of both. First one is a plugged PCV valve , the other is bad ring seal. Remove the breather cap and PCV and start the motor up, let it get warmed up and then revved the motor up from idle to around 4000 RPM several times rapidly, if the smoke from the valve covers increases each time you rev it up it is blowby Let us know what you find, also has this motor set for a long time before you started driving it? A very simple way to check the PCV valve is to put your finger over the hole in the bottom with the motor running, if the idle speed decreases it is working, your plugging a metered vacume leak If it doesn't change the idle speed it, the PCV valve or hose, is plugged up Let us know what you find
Posted By: frank

Re: Oil blowing out of breather - 11/27/14 11:54 PM

Quote:

Do you have a pcv valve on the car?

Are the baffles in the valve covers?




No PCV valve and the valve covers have baffles
Posted By: lewtot184

Re: Oil blowing out of breather - 11/28/14 12:29 AM

sounds like it's time for a cylinder leak down test.
Posted By: QTR MILR

Re: Oil blowing out of breather - 11/28/14 01:57 AM

Could be a bad head gasket.... Been there done that...
Posted By: RapidRobert

Re: Oil blowing out of breather - 11/28/14 02:15 AM

Quote:

No PCV valve


What do you have for crankcase ventilation? If none at all, just normal blowby will cause your symtoms
Posted By: frank

Re: Oil blowing out of breather - 11/28/14 03:48 PM

Quote:

Quote:

No PCV valve


What do you have for crankcase ventilation? If none at all, just normal blowby will cause your symtoms




Just the breather. I cant find a PCV that fits in this valve cover. Engine has 300 miles and runs perfect

Attached picture 8344345-breather.jpg
Posted By: Challenger 1

Re: Oil blowing out of breather - 11/28/14 05:15 PM

You must have a PCV system hooked up otherwise you run the risk of blowing out gaskets and it will always leak oil no matter how many breathers you have, imo..

Here's how I did it 25 years ago with cast valve covers. Drilled the right sized hole for the grommet with a hole saw. And bolted in this baffle. I used this valve cover for 20+ years on my car. The baffle worked great.

I learned about PVC valves on my first 340 which came with these cast covers with no PCV hole. They were black and shinny like yours. I fought oil leaks for a while until a mechanic told me it needed it.
So drilled that hole and got a grommet out of a stock valve cover and it stopped my oil leaks and more. Made a difference for the good and I became good friends with that mechanic. You can get that grommet at most "help" sections at auto parts stores. All PCV grommets were the same in those years.
Posted By: rustbuckett68

Re: Oil blowing out of breather - 11/28/14 08:02 PM

Had the same problem in my old van, along with a miss. Compression check showed a dead hole, air pressure blew into the crankcase. Head gasket was iffy, but turned out to be broken rings (about 20 pieces). Only reason I caught it was I noticed some roughness on the edge of the piston where some small pieces left home. Cylinder wall was good. I swore that if I had to do it again, the engine is coming out!
Posted By: TJP

Re: Oil blowing out of breather - 11/28/14 08:11 PM

Quote:

You must have PCV system hooked up otherwise you run the risk of blowing out gaskets and it will always leak oil.




You don't have to have a PCV but it is a good idea for many reasons.

If you don't have a PCV you DO HAVE to HAVE adequate crankcase ventilation though IE: non restrictive breather(s)

All engines develop a certain amount of Blow by. The PCV and or breathers relieve this pressure that would otherwise continue to build up inside the crankcase and eventually begin blowing gaskets seals etc.
If an engine is developing excessive amounts of blowby it is normally due to poor ring seal or a head gasket. A leak down test will establish which of the two is the culprit.
based on your description either your existing breather is very restricted or you have excessive crankcase pressure.

Posted By: Cab_Burge

Re: Oil blowing out of breather - 11/28/14 10:00 PM

You can buy a rubber grommet that will fit into the valve covers for the PCV valve that will allow you to run another pushin breather cap like your running now, I do that on my race motor running E85 I use two twistin and two pushin breather caps, not the twistin non breather cap like your using now I have a set of those valve covers your using on another street motor I have, I'm using a PCV valve on it If you want I can verify which rubber grommet I used to make the stock Mopar PCV valve fit into those valve covers. I probally have one of those in stock

Attached picture 8344673-SANY0276.JPG
Posted By: frank

Re: Oil blowing out of breather - 11/28/14 10:22 PM

Quote:

You can buy a rubber grommet that will fit into the valve covers for the PCV valve that will allow you to run another pushin breather cap like your running now, I do that on my race motor running E85 I use two twistin and two pushin breather caps, not the twistin non breather cap like your using now I have a set of those valve covers your using on another street motor I have, I'm using a PCV valve on it If you want I can verify which rubber grommet I used to make the stock Mopar PCV valve fit into those valve covers. I probally have one of those in stock




Could you please

Appreciate all the information
Posted By: TJP

Re: Oil blowing out of breather - 11/28/14 11:29 PM

I would still encourage a leak down test just to verify the ring seal is good. blowing oil out of a breather cap, especially with baffle in place is usually not a good sign. Leak down testers are relatively inexpensive.
I also would encourage the use of a PCV on a street engine.
Good luck and keep us posted
Posted By: Cab_Burge

Re: Oil blowing out of breather - 11/29/14 02:28 AM

Quote:

I would still encourage a leak down test just to verify the ring seal is good. blowing oil out of a breather cap, especially with baffle in place is usually not a good sign. Leak down testers are relatively inexpensive.
I also would encourage the use of a PCV on a street engine.
Good luck and keep us posted


Not all machine shops use a torque plate when finishing the final bore preperation, it shouldn't blow the oil out of your motor now as long as you have two breather caps on it, do you?
Posted By: 383man

Re: Oil blowing out of breather - 11/29/14 02:54 AM

Quote:

Quote:

You must have PCV system hooked up otherwise you run the risk of blowing out gaskets and it will always leak oil.




You don't have to have a PCV but it is a good idea for many reasons.

If you don't have a PCV you DO HAVE to HAVE adequate crankcase ventilation though IE: non restrictive breather(s)

All engines develop a certain amount of Blow by. The PCV and or breathers relieve this pressure that would otherwise continue to build up inside the crankcase and eventually begin blowing gaskets seals etc.
If an engine is developing excessive amounts of blowby it is normally due to poor ring seal or a head gasket. A leak down test will establish which of the two is the culprit.
based on your description either your existing breather is very restricted or you have excessive crankcase pressure.







I agree with this as many racers in the older days just used breathers when the cams they used did not pull much vacum and for race engines which are wide open most of the time there is no vacum anyway at wide open throttle so they would use good breathers on their engs and sometimes they used 4 breathers with 2 on each valve cover. I dont use a PCV on the eng in my 63 right now since it does not pull alot of vacum with the cam I use. I use a good breather on each valve cover and it has worked fine for me with this eng. I prefer to use a PCV on a street eng but with a low vacum that big enough cams cause the PCV may not work good. Many racers use the check valves in the header collectors with a hose to the breathers to draw fumes out but on a street car like mine with a full exh system it will not work to well. Course today many serious racers making alot of power use a vacum pump to create a vacum in the crankcase and pick up some extra hp. But I agree that most street engines pull enough vacum and can use a PCV system which they should. You should be able to do like some on here said and find a gromett to fit one of your valve covers to hook a PCV valve in. Ron
Posted By: RapidRobert

Re: Oil blowing out of breather - 11/29/14 03:07 AM

OT but for reference it is a good read on ring seal. "breakin secrets" at www.mototuneusa.com
Posted By: frank

Re: Oil blowing out of breather - 11/29/14 03:16 AM

Quote:

Quote:

I would still encourage a leak down test just to verify the ring seal is good. blowing oil out of a breather cap, especially with baffle in place is usually not a good sign. Leak down testers are relatively inexpensive.
I also would encourage the use of a PCV on a street engine.
Good luck and keep us posted


Not all machine shops use a torque plate when finishing the final bore preperation, it shouldn't blow the oil out of your motor now as long as you have two breather caps on it, do you?




No only one breather. Torque plate was used on this engine. The break in was done on the dyno. I didn't use a PCV because I could not find one to fit these MP valve covers.
Posted By: Challenger 1

Re: Oil blowing out of breather - 11/29/14 03:24 AM

Quote:

OT but for reference it is a good read on ring seal. "breakin secrets" at www.mototuneusa.com




I have never read the entire link, it's a good one. But I think your saying? or they are saying a PCV will help the rings seat better just like a vacuum pump on a much smaller scale?

Either way that's my opinion for a street car, that a PCV valve will help the rings.
Posted By: Challenger 1

Re: Oil blowing out of breather - 11/29/14 03:30 AM

Can you post a picture of the passenger side valve cover?
Posted By: Cab_Burge

Re: Oil blowing out of breather - 11/29/14 03:45 AM

You have a PM
Posted By: RapidRobert

Re: Oil blowing out of breather - 11/29/14 04:44 AM

Quote:

Quote:

OT but for reference it is a good read on ring seal. "breakin secrets" at www.mototuneusa.com




I have never read the entire link, it's a good one. But I think your saying? or they are saying a PCV will help the rings seat better just like a vacuum pump on a much smaller scale?

Either way that's my opinion for a street car, that a PCV valve will help the rings.


Actually I was not thinking of a connection between the PCV and ring breakin just that the mention of blowby made me think of that article which sounds very very convincing (to me), that the quality of the ring breakin (good fair or bad) is going to be determined in that very narrow (time) window. My next one I'm gonna gun it repeatedly as they talk about (& a leakdown before breakin/after breakin & at later intervals).
Posted By: pro-streeter

Re: Oil blowing out of breather - 11/29/14 05:33 AM

Add the PCV as suggested. Connect it to manifold or carb base vacuum. You will need to drill the valve cover and add the baffle. Mopar performance has the PCV grommet and baffle kit for those valve covers.
Good Luck
Posted By: frank

Re: Oil blowing out of breather - 11/29/14 07:43 PM

Quote:

Can you post a picture of the passenger side valve cover?




Attached picture 8345496-pasvc.jpg
Posted By: challengermike

Re: Oil blowing out of breather - 11/30/14 05:35 AM

You can get a twist in pcv valve that looks like a breather, autoparts stores sell them or get a different grommet for the blockoff grommet you have on the pass side valve cover.
Posted By: Dcuda69

Re: Oil blowing out of breather - 11/30/14 06:35 AM

This topic has been beat to death over the years on here. PCV valves are very helpful on street engines to help ventilate the crankcase. PCV valves flow max amounts at low vacuum(wot) conditions. They flow less at closed throttle(high vacuum) conditions....check it out!

https://www.google.com/search?q=pcv+valv...mp;ved=0CCQQsAQ
Posted By: Cab_Burge

Re: Oil blowing out of breather - 11/30/14 08:50 AM

Quote:

This topic has been beat to death over the years on here. PCV valves are very helpful on street engines to help ventilate the crankcase. PCV valves flow max amounts at low vacuum(wot) conditions. They flow less at closed throttle(high vacuum) conditions....check it out!

https://www.google.com/search?q=pcv+valv...mp;ved=0CCQQsAQ


Me thinks you have the flow backwards, maximum at idle to part throttle, no or almost no flow at WOT that is according to all the vacume gauges I've used over the years
Posted By: cogen80

Re: Oil blowing out of breather - 11/30/14 01:45 PM

Quote:

Quote:

Can you post a picture of the passenger side valve cover?







try a fram fv184 valve.

http://shop.advanceautoparts.com/p/fram-pcv-valve-fv184/22660083-P
Posted By: Dcuda69

Re: Oil blowing out of breather - 11/30/14 04:26 PM

Quote:

Quote:

This topic has been beat to death over the years on here. PCV valves are very helpful on street engines to help ventilate the crankcase. PCV valves flow max amounts at low vacuum(wot) conditions. They flow less at closed throttle(high vacuum) conditions....check it out!

https://www.google.com/search?q=pcv+valv...mp;ved=0CCQQsAQ


Me thinks you have the flow backwards, maximum at idle to part throttle, no or almost no flow at WOT that is according to all the vacume gauges I've used over the years




Take a look at the link I posted. I understand vacuum drops under load....however the flow through the valve increases because of spring tension. They do that because,as you know, the engine produces more blow-by under load. I have posted pics of the flow through the valve on numerous occasions, I just don't have them on this pc. The link has many of the same pics.
Posted By: Mr.Yuck

Re: Oil blowing out of breather - 11/30/14 06:58 PM

Quote:

Quote:

Oil is blowing out the breather located in the left valve cover. Its enough to puddle on the floor after I drive the car for about 5 or more miles. What is causing this and how do I fix it?


Crankcase pressure is the only reason that oil will be blown out of the breather caps Two possible causes, possibly a combination of both. First one is a plugged PCV valve , the other is bad ring seal. Remove the breather cap and PCV and start the motor up, let it get warmed up and then revved the motor up from idle to around 4000 RPM several times rapidly, if the smoke from the valve covers increases each time you rev it up it is blowby Let us know what you find, also has this motor set for a long time before you started driving it? A very simple way to check the PCV valve is to put your finger over the hole in the bottom with the motor running, if the idle speed decreases it is working, your plugging a metered vacume leak If it doesn't change the idle speed it, the PCV valve or hose, is plugged up Let us know what you find




bad rings or burned pistion... ask me how I know. Like mentioned you need a leak down. sorry
Posted By: 383man

Re: Oil blowing out of breather - 12/01/14 04:52 AM

Quote:

Quote:

Quote:

This topic has been beat to death over the years on here. PCV valves are very helpful on street engines to help ventilate the crankcase. PCV valves flow max amounts at low vacuum(wot) conditions. They flow less at closed throttle(high vacuum) conditions....check it out!

https://www.google.com/search?q=pcv+valv...mp;ved=0CCQQsAQ


Me thinks you have the flow backwards, maximum at idle to part throttle, no or almost no flow at WOT that is according to all the vacume gauges I've used over the years




Take a look at the link I posted. I understand vacuum drops under load....however the flow through the valve increases because of spring tension. They do that because,as you know, the engine produces more blow-by under load. I have posted pics of the flow through the valve on numerous occasions, I just don't have them on this pc. The link has many of the same pics.





The PCV flows a small amout at idle because the vacum is high and it pulls the pintle in very far. It flows the most at part throttle when vacum is a little lower then at idle but it has to have some vacum to pull the pintle valve part the way from the back of the valve because at wide open throttle with no vacum the spring closes the valve to the back of it for no flow at WOT and no vacum. It also does that so on a backfire the valve will seat and keep any backfire out of the crankcase. Ron
Posted By: m88mark

Re: Oil blowing out of breather - 12/01/14 06:33 AM

Quote:

You can get a twist in pcv valve that looks like a breather, autoparts stores sell them or get a different grommet for the blockoff grommet you have on the pass side valve cover.


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