Leaky Breather

[DocG]

First, let me introduce myself to the wonderful world of 5.0 Tech! I'm a long time listener, first time caller. I recently picked up a 92 LX with some goodies. I'll post a pic up at the end. Fresh block bored to 306 with the Holley Systemax kit. All the suspension goodies you could dream up, pretty darn fresh paint, and a thousand other new little bits and pieces on it.

Anyways, on to the Tech. I noticed oil coming out of the breather. It has a KN breather filter on it. I've heard from several of my car buddies that this is fairly normal on an engine like this. Figured it never hurts for more opinions. I'm seeing anywhere from a few drops on the driveway to a 2 inch wide spot after each drive. Plus the smell of oil burning off the headers in the morning just doesn't make my day.

So is this amount of oil normal? The breather filter is a bit loose, so maybe it has the wrong grommet on it.

Heard about a catch pan that fits under the breather to catch the extra....anyone ever heard of this?

I'm not thinking its a big deal, but don't want to keep dripping oil in my garage and driveway.

Thanks ladies and gents!

 

[HISSIN50]

We assume you don't have a PCV and breathers mixed (another issue for another time, if so).

Do you know why there is no PCV system still in place? When PCV's get overwhelmed (because of another issue), people often go to a breather [or six].

As for the mess, you might want to convert to a closed breather with a remote dump (which can be into a catch can, to keep oil off the ground). Otherwise, I like your idea to get that grommet situation fixed and be sure there is adequate baffling under the breather opening.

Good luck and bump for you.

 

[DocG]

Thanks! I'm going to try to stop today and pick up a new breather. That one on it has the grommet built in so I can't swap to a new one. The grommet on the existing one is a bit chewed up. The existing breather is also a straight shot into the filter on it. No baffling on the grommet, nothing. Hopefully this will help at least keep it from leaking so much.

I have no idea why there is no PCV system in place. Not sure how well you can see in the attached picture, but all that there is in place is the breather. The engine was built two owners ago by a pretty reputable local mustang shop. I have all the documention of the parts and build for everything but the shortblock itself. Not sure what type of pistons, rods, crank, etc. are in the bottom end. The top end is all Holley Systemax pretty much.

I've seen the remote dump setups before, might check into that.

As I'm sure you can tell, I'm not much of an expert on engines and engine work.

Thanks again for your reply. This Stang has had a lot of work and I'm still trying to figure out what all is on it and where to go from here!

 

[strtrcr50]

Doc, check to see if there's a pcv valve in the back of the intake and if it's hooked up to vaccuum. Check page 17 of this link for a vaccum diagram.
http://www.jegs.com/InstallationInstructions/500/510/510-300-501-1.pdf

 

[DocG]

I'll have to look more closely at that setup when I get home. I know there are several vacuum fittings on the intake that are just blocked off and not being used right now.

 

[strtrcr50]

Odds are, you DO have a pcv valve hooked up and if so, you really shouldn't run a breather. I don't really know how to describe where it's located and I really don't know on a systemax intake. Just that it's at the very back of the intake manifold slightly towards the passenger side.
Also, you prob don't have any baffles in your valve cover and the oil is splashing right up the tube. Take off the breather and look down the hole. If you see a rocker, there is no baffle.

 

[DocG]

Odds are, you DO have a pcv valve hooked up and if so, you really shouldn't run a breather. I don't really know how to describe where it's located and I really don't know on a systemax intake. Just that it's at the very back of the intake manifold slightly towards the passenger side.
Also, you prob don't have any baffles in your valve cover and the oil is splashing right up the tube. Take off the breather and look down the hole. If you see a rocker, there is no baffle.

Interesting. It did have an extra valve cover with it....I'd have to check to see if it is a passenger side and whether it has the breather hole in it.

There are no baffles, I've pulled the breather a couple times and I see rocker arms. Like you said, this is why the oil just splashed right up and out...especially with the breather being loose.

I'll check for the pcv.....the diagram seemed to make sense. Seems like its just supposed to run out of the front of the intake, through a collector, and back into the intake based on that diagram. Ya know...I have a feeling mine doesn't have that hooked up because I don't remember seeing any sort of collector.

 

[strtrcr50]

Yours is definitely missing the hose that goes from the throttle body to the oil filler neck if that's what you are referring to. I'm not sure why they wouldn't have that hooked up except because they wanted to run a breather. The only reason I know not to hook it up that way is if you have a blower. Leaving that hooked up would pressurize the crankcase under boost.

 

[DocG]

I don't know....guess thats the problem with buying a car that's had so much work done on it. I'm not 100% what has been done or why!

Plus I'm just now learning my way around a 5.0 engine so I'm doubly fugged.

 

[strtrcr50]

Well, at least the 5.0 engine is very easy to work with. The only thing I can think of is that since the car is splashing oil up the filler neck, they eliminated the line because the car was sucking oil down it and smoking out the pipes. I wonder if you could rig a baffle somehow?
On edit, does your car have an oil filler neck or is the breather installed right into the valve cover?

 

[strtrcr50]

Do your valve covers look like this?
1)

or this
2)

I mean in regards to where the breather goes.

 

[DocG]

Breather is straight on the valve cover. I picked up a cheap $5 one from Pep Boys.....it fits much tighter. The other one had a wore out grommet so that could be part of why it was leaking out so much.

Still question the whole PCV setup though. Not sure what's normal. I eyeballed the lines based on your diagram srtrcr and it seems like the line comes out the front, goes underneath, connects to what looks like it'd be a self-standing PCV valve, and another line exits the valve and goes to some sort of sensor and "box" in the front lower passenger area of the engine bay. Again, I guess I'm used to PCV valves going into a manifold or intake or something...although this may be normal.

If its normal, then I guess I'd probably set. The PCV is setup and if the new breather stops the oil flow....golden.

I did pick up a oil separator from HD along with some hardware. Need to pickup some hose and I could run my own oil dump for it too.

 

[strtrcr50]

Technically, you have the wrong valve covers. This is why they didn't run the vaccuum line. Nowhere to attach it. The PCV valve should be plugged into the back of the intake manifold. Here is what my intake looks like. Yours should be somewhat similar. Notice the hole in front of the intake runners. This is where the pcv valve should be. This picture is the back of the engine by the way.

Here's a picture of your intake and you can see the pcv hole.

What does yours have there?

 

[DocG]

Ok, if I'm looking in the right spot at the very rear end of the lower manifold, I think I'm spotting the PCV valve....its tough to get a good view back there.

The vacuum lines are routed kinda weird. I'll have to take some pics to show you what I'm talking about tomorrow. But based on the diagram in your link earlier...from the back side of the upper, the line goes to the vacuum tree, but splits off on its way to what I'm spotting as the PCV valve, or something that looks like its plugged into the lower.

The front of the upper, a line goes underneath to the back to some sort of free standing valve, then comes back to the front of the car and down to the bottom to some sort of sensor and a box.

 

[strtrcr50]

Ok. Looks like you do have a PCV valve. Which means you shouldn't be running a breather. Think about it this way. Now the PCV valve can pull in air into the intake manifold that hasn't been measured by the mass air meter. Basically, the car has a vaccuum leak.

 

[DocG]

Ok. Looks like you do have a PCV valve. Which means you shouldn't be running a breather. Think about it this way. Now the PCV valve can pull in air into the intake manifold that hasn't been measured by the mass air meter. Basically, the car has a vaccuum leak.

Could you explain to my tired brain? How would it be pulling air into the intake that hasn't been measured?

Backwards through the breather?


The car did come with an extra valve cover....seemed odd to have just one brand new extra, maybe it'll come in handy!

 

[strtrcr50]

Could you explain to my tired brain? How would it be pulling air into the intake that hasn't been measured?

Backwards through the breather?


The car did come with an extra valve cover....seemed odd to have just one brand new extra, maybe it'll come in handy!

Correct. The vaccuum pulled at the lifter valley will pull through the breather.

 

[DocG]

Correct. The vaccuum pulled at the lifter valley will pull through the breather.

If that were the case, I don't think I'd expect so much oil to be coming out of the breather....hmm....

This car has some mysteries!

 

[DocG]

Ok, I've spent like the last 3 hours reading many of the debate threads on running only a closed PCV system vs. running the standard PCV system with an open breather. My head is spinning!

I've got the new breather on now that fits better and haven't seen any leaks, but I see the case where it could still cause some tuning issues.

I might try to find a cheap closed breather cap of some sort. Obviously I need some sort of removable cap there if I ever want to put oil in the car. Problem is....the closed ones all seem to have a vent on them that I've read needs to goto the CAI or somewhere. My CAI doesn't have any holes in it.....can I connect this to one of the empty plugs on my intake? Is this meant to be part of the vacuum system?

I'm guessing this is similar to the plug on the stock oil filler neck on stock motors. Where do they connect the tube too?

Thanks again, seems like this issue comes up many times and I've gotten past my original question, but I want to make sure this vacuum system on mine is setup right so if I do need to tune it, I'm working from the right foundation.

 

[strtrcr50]

If that were the case, I don't think I'd expect so much oil to be coming out of the breather....hmm....

This car has some mysteries!

Under full throttle/hard acceleration/high rpms, there is very little/no vaccuum. However, those rockers are throwing a lot of oil.

I might try to find a cheap closed breather cap of some sort. Obviously I need some sort of removable cap there if I ever want to put oil in the car. Problem is....the closed ones all seem to have a vent on them that I've read needs to goto the CAI or somewhere. My CAI doesn't have any holes in it.....can I connect this to one of the empty plugs on my intake? Is this meant to be part of the vacuum system?

It's not on your cold air intake. If you look at your throttle body, you'll see a capped vaccuum port on top. That's where it goes. Ideally, you would put on a set of valve covers designed for a fuel injected motor which will have the baffle and the filler tube and vac port. However, I forget which rockers you have and they may not clear the baffle.