PCV Sucking oil into intake? need answers

[latham83]

Hey i had to pull apart my engine for a longgg ass story but anyways, most of my parts are new and have like 500 miles on them , but the runner on my gt-40 intake, the lower...number 6 runner is covered in oil, as also the passageway down through the head for number 6..that was covered in oil also..and number 6 piston was very carboned or oiled up....
i was told to check my pcv valve...now i pulled out the screen and it was soaked in oil pretty good....if this is old which it is...could that just suck oil up through there into one runner?? number 3 had alittle more than the others..but not like 6 was...it was pretty gunked...
what else could i check for ??
what is that baffle you guys are talking about that you have to switch from the stock to gt-40 lower intake or something??? u mean the screen? same name?

 

[latham83]

..

 

[HISSIN50]

i think the baffle and screen are terms used interchangably, but im not positive. i would make sure you atleast have the screen. older ones can look like poo.

common to have lots of oil in the upper intake (and lower accordingly). what i might do: run a wet and dry compression test on the motor, noting the cylinders you suspect as having a lot of blowby. if those cylinders have a big jump from dry to wet compression numbers, you probably have some blowby (more than normal, perhaps) in those cylinders.

you can also run a catch can and filter on the pvc if you want. good luck.

 

[Scott_B]

I changed my PCV and screen today as well. The screen was pretty gunky! I also run an oil seperator filter and have found oil in it. Havent driven the car since i swaped pcv's. Hope it helps some!

 

[latham83]

hmm...yea but does it make sense for just number 6 runner's and piston to be gunked with oil/carbon? and not the others? where does the passage where the pcv goes into link too on the gt-40 intake..anyone kno?

 

[Michael Yount]

The baffle and the screen are two different things as far as I use the terminology. The baffle is a flat piece of sheet metal that is fastened to the bottom of the lower intake that would block any oil physically splashing around the back of the lifter valley from contacting the backside of the intake, or from being able to be drawn into the pcv circuit. The screen is a simple oil trap - as oily vapors are sucked out of the lifter valley through the pcv, they must pass through the screen - which "traps" small droplets of oil, and lets them drop back into the lifter valley (back onto the the baffle) where the oil is returned to the engine. It's not 100% effective, but it should knock most of the oil out of the stream. If you're gonna renew the pcv system - buy new hose, a new screen, a new valve and a new rubber grommet. I'd get them all from Ford (get the hose anywhere) as the aftermarket grommets/pcv valves are bad for not fitting together snugly enough and causing vacuum leaks. If that doesn't do the trick, install a catch can in between the pcv valve and the intake manifold to further trap/knock out the oil from the line before it enters the manifold.

 

[YummyRide]

I had a similar problem with a completely different car, a jeep wrangler. What fixed that is what Michael is talking about, sort of a vacum issue. Might as well change out as much as you can while you're there. And use the Ford parts.

 

[latham83]

yea ill change those out and see if that solves it...
um..question..i know arp head bolts can be reused..this would be the 3rd time though..is that ok? i really dont have money or time to buy new ones ..but id like to kno...

 

[Michael Yount]

As long as they haven't been overtorqued and yielded, they should be fine to go again.

 

[millhouse]

I had the same problem.

After checking the intake to insure the baffle was in place (I couldnt remember if it had been there when I installed it), cleaning the snot out of the upper intake & tb, soaking the screen in some simple green (best degreaser on the planet earth )...I then decided to install a air/oil seperator.

Here it is in all it's glory after a weeks worth of daily commuting (60 miles per day, a 80+mph).

 

[Mavrick]

I had the same problem.
Here it is in all it's glory after a weeks worth of daily commuting (60 miles per day, a 80+mph).

Damn you drive almost 500km every week in your Mustang? That is quite a bit of oil that you would have been burning too... maybe this is where the oil is dissapearing from in most everyone's 5.0L motors?

 

[millhouse]

Damn you drive almost 500km every week in your Mustang? That is quite a bit of oil that you would have been burning too... maybe this is where the oil is dissapearing from in most everyone's 5.0L motors?

Yeah, I actually drive over 400 miles per week. It's better than when I was driving over 1000 miles per week for three months (120miles one way) .

I do still burn some oil though. It's one of the evils of having 3.73 gears and a heavy foot at freeway speeds.

 

[Michael Yount]

Millhouse - That's amazing to me; and your motor's basically stock. How many miles on the car? Do you have a sense if you're getting more blowby than the average motor? I've got catch cans on mine (less elegant version of the separator) -- but on the normal 3-4000 miles between changes, my oil level sits right on the full line the whole time. I can't be using/burning/leaking/pcv-ing more than a couple of tablespoons of oil over that long a period. How often/at what rate do you have to add oil to the motor? Is that all oil? Is there any condensate in it? Most of what I drain out of my catch can is dark in color - but I believe it's more condensate than anything else.

 

[millhouse]

Millhouse - That's amazing to me; and your motor's basically stock. How many miles on the car? Do you have a sense if you're getting more blowby than the average motor? I've got catch cans on mine (less elegant version of the separator) -- but on the normal 3-4000 miles between changes, my oil level sits right on the full line the whole time. I can't be using/burning/leaking/pcv-ing more than a couple of tablespoons of oil over that long a period. How often/at what rate do you have to add oil to the motor? Is that all oil? Is there any condensate in it? Most of what I drain out of my catch can is dark in color - but I believe it's more condensate than anything else.

Lol, I'm quickly approaching 200k (only have a couple thousand to go).

Yes, I do believe I'm getting more blowby than the average motor. I'd I put a quart in every two weeks or so. Keep in mind though that I'm running constantly at 2700 rpms for 30 miles per...which doesnt help in the least bit.
I also have well over 150 total wot runs down the 1/4...starting when she had 160k on the odo.

I'd say that most of what you see in the picture is oil. Weather it's from the piston rings or valve guides is yet to be determined. The only time I blow any smoke is when I go downshift and go wot from a roll...and even then it's only black smoke. She seems to be running rich which is just fine by me.

 

[gt90stang]

My PCV was sucking quite allot of oil also. I installed a restrictor in the tube that goes between the TB and oil filler. The restrictor has about a 1/8" hole and really reduced my oil consumption. I think I am going to try a 1/6" hole next to see how it works. Just make sure your restrictor can't be blown or sucked into the TB or filler, it must be a snug fit.

Good Luck, Don

 

[Michael Yount]

millhouse - that explains the oil; man do you ever go through it! Considering my tire size, mine's about like a Mustang with 3.91 gears; so I'm turning over a little less rpm than you - at 70 I'm around 2400-2500 rpm. But I guess with fewer miles (only 64k on my motor) mine's just not using a drop of oil.

 

[millhouse]

millhouse - that explains the oil; man do you ever go through it! Considering my tire size, mine's about like a Mustang with 3.91 gears; so I'm turning over a little less rpm than you - at 70 I'm around 2400-2500 rpm. But I guess with fewer miles (only 64k on my motor) mine's just not using a drop of oil.

She's a hungry beast...and I feed her well