OIL in the airbox? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 09-11-2011, 12:39 PM   #1
Member
 
Join Date: Aug 2011
Posts: 51
OIL in the airbox?

Went to change the filter today found oil soaked in the filter...looks like it was making its way in from the line off the top of the engine. Is this common?

Davers87 is offline   Quote Quick Reply
Old 09-11-2011, 01:24 PM   #2
Jeeper
 
chensley's Avatar
 
Join Date: Jun 2010
Location: Mississippi
Posts: 444
Quote:
Originally Posted by Davers87 View Post
Went to change the filter today found oil soaked in the filter...looks like it was making its way in from the line off the top of the engine. Is this common?
It's not good. Its it a lot of oil?

What you are seeing is referred as "oil blow by", which means that a gap has formed between the piston and the cylinder walls. You'll notice a loss of power along with oil in the air box. You will ultimately have to either A.) See if you can replace the piston rings and re hone the cylinders B.) Replace the engine.

chensley is offline   Quote Quick Reply
Old 09-11-2011, 01:33 PM   #3
Jeeper
 
Join Date: Aug 2011
Location: Utah
Posts: 88
I respectfully disagree. Blowby goes out the pipe. When it backs through the vent into the intake its a pressure (crank case venting) issue. EPA had mandated the fumes go back into the intake air to be reburned. Its usually an easy fix
__________________
Location: 3 Hours from Little Sahara Dunes
4 Hours from St. Anthony Dunes
4.5 hours from MOAB
DamnBigPapa is offline   Quote Quick Reply
Old 09-11-2011, 01:38 PM   #4
Jeeper
 
Yjwolf's Avatar
 
Join Date: Oct 2010
Posts: 466
Quote:
Originally Posted by DamnBigPapa
I respectfully disagree. Blowby goes out the pipe. When it backs through the vent into the intake its a pressure (crank case venting) issue. EPA had mandated the fumes go back into the intake air to be reburned. Its usually an easy fix
I agree. I've heard that it's caused by the vent lines being clogged which leads to uneven pressure in the top end causing the oil to get in the line to the airbox
Yjwolf is offline   Quote Quick Reply
Old 09-11-2011, 01:49 PM   #5
Jeeper
 
88Sahara's Avatar
 
Join Date: Jun 2010
Location: Henryville, IN
Posts: 182
Had the same thing. Could even smell the oil when I got up to operating temp. Took the breather off and cleaned it up, replaced the PCV and cleaned out the hoses both in and out of the breather and it immediately fixed the problem.
88Sahara is offline   Quote Quick Reply
Old 09-11-2011, 03:15 PM   #6
Jeeper
 
Django Unleashed's Avatar
 
Join Date: Sep 2011
Posts: 18
Yep, change the pcv. If it were coming in from the bottom then you would have issues.
Django Unleashed is offline   Quote Quick Reply
Old 09-11-2011, 03:21 PM   #7
2xs
Cali Smog Nazi.

WF Supporting Member
 
2xs's Avatar
 
Join Date: Jun 2011
Location: Santa Rosa, Ca.
Posts: 2,679
Images: 3
Quote:
Originally Posted by DamnBigPapa View Post
I respectfully disagree. Blowby goes out the pipe. When it backs through the vent into the intake its a pressure (crank case venting) issue. EPA had mandated the fumes go back into the intake air to be reburned. Its usually an easy fix
Wow, misinformation...

That line that is dumping oil onto your air filter is a breather for the PCV, if your PCV is plugged, it cane vent the vapors from your crankcase (those vapors are created from blow-by through the piston rings). Without that breather pipe, your PCV valve would force a vacuum in your engine crankcase and suck in your seals, creating a bigger leak.

Check your PCV valve and hose, you should have manifild vacuum at the end of the hose where the PCV valve attaches to, when you install hte valve, you should get manifold vacuum out the other end, and you can easily verify this by putting your finger over the end that sticks into the grommet on top of the valve cover.

The breather pipe is NOT meant to vent fumes so they can be burnt by the engine, thats the job of the PCV system via the PCV valve.
2xs is offline   Quote Quick Reply
Old 09-11-2011, 04:06 PM   #8
likes relays

WF Supporting Member
 
onroad's Avatar
 
Join Date: Jul 2011
Location: Long Island, NY
Posts: 347
The crankcase ventilation on these use a metered orifice, the threaded fitting on the intake manifold. The hose on the valve cover to that fitting pulls vacuum, and gases from the crankcase back into the intake manifold.

The other hose, from the valve cover to the airbox, draws fresh air INTO the crankcase. Completing the system.

The fitting on the manifold has a small machined hole which limits the amount of vacuum it pulls on the crankcase. That commonly gets clogged. When that happens, the blowby gases, carrying oil particles, are pushed out the wrong way, back into your airbox.

I'd pull the fitting and see if it's clogged.
__________________
---Greg
1993 YJ Off Death Row
Photography...other
onroad is offline   Quote Quick Reply
Old 09-11-2011, 06:16 PM   #9
Newb
 
corey_gullion's Avatar
 
Join Date: Sep 2011
Posts: 4
my 94 yj also has this problem so all i need to do is get a new pcv valve and clean the hoses and it will be fixed? does this also cause loss of power???
corey_gullion is offline   Quote Quick Reply
Old 09-11-2011, 06:21 PM   #10
Jeeper

WF Supporting Member
 
jk'n's Avatar
 
Join Date: Jan 2009
Location: First Quadrant in the Land of the Free
Posts: 4,790
Quote:
Originally Posted by corey_gullion View Post
my 94 yj also has this problem so all i need to do is get a new pcv valve and clean the hoses and it will be fixed? does this also cause loss of power???
Did you miss onroad's post?

X2 on what he said.
__________________

Participate in life....Keep movin'....Go there....JK'n it.........Do it! Jeep #1: Red Rock 08 JK Rubicon 4dr, 6 sp manual, Stock Mud Tires, MyGIG Upgrade, Hard Top, after sale BestTop SunRider Soft Top, Congo Cage Rack, Mopar slush mats Jeep #2 Black 08 JK Rubicon 2dr, 6 sp manual, both tops, some chrome...uggg (my wife's jeep) Jeep #3 White 92 YJ (my son's jeep) A great quote from a good friend: "All hail click clack and master jk'n." Click and clack are my idols!
jk'n is offline   Quote Quick Reply
Old 09-11-2011, 06:29 PM   #11
Jeeper
 
Razortag87's Avatar
 
Join Date: Sep 2011
Posts: 18
Valve seals could be bad causing pressure in crank case
Razortag87 is offline   Quote Quick Reply
Old 09-11-2011, 07:02 PM   #12
Jeeper

WF Supporting Member
 
jk'n's Avatar
 
Join Date: Jan 2009
Location: First Quadrant in the Land of the Free
Posts: 4,790
Crank case ventilation would be more sudden than valve seals though so it could be recognized by how this came on....suddenly or gradually.
__________________

Participate in life....Keep movin'....Go there....JK'n it.........Do it! Jeep #1: Red Rock 08 JK Rubicon 4dr, 6 sp manual, Stock Mud Tires, MyGIG Upgrade, Hard Top, after sale BestTop SunRider Soft Top, Congo Cage Rack, Mopar slush mats Jeep #2 Black 08 JK Rubicon 2dr, 6 sp manual, both tops, some chrome...uggg (my wife's jeep) Jeep #3 White 92 YJ (my son's jeep) A great quote from a good friend: "All hail click clack and master jk'n." Click and clack are my idols!
jk'n is offline   Quote Quick Reply
Old 09-11-2011, 08:22 PM   #13
Jeeper
 
Django Unleashed's Avatar
 
Join Date: Sep 2011
Posts: 18
Quote:
Originally Posted by onroad View Post
The crankcase ventilation on these use a metered orifice, the threaded fitting on the intake manifold. The hose on the valve cover to that fitting pulls vacuum, and gases from the crankcase back into the intake manifold.

The other hose, from the valve cover to the airbox, draws fresh air INTO the crankcase. Completing the system.

The fitting on the manifold has a small machined hole which limits the amount of vacuum it pulls on the crankcase. That commonly gets clogged. When that happens, the blowby gases, carrying oil particles, are pushed out the wrong way, back into your airbox.

I'd pull the fitting and see if it's clogged.
Thanks onroad, I learned something new today. Good post!
Django Unleashed is offline   Quote Quick Reply
Old 09-12-2011, 01:26 PM   #14
Member
 
Join Date: Aug 2011
Posts: 51
there was not alot of oil I changed the filter anyway and havent noticed any oil on the new one yet. There are oil spots right under the hose that connects to the front left side of the airbox and oil spot out of the hose comeing from the furthest back elbow out of the valve cover.

Do the elbows out of the valve cover pull strait out along with the grammets...i feel like if I pull harder than I am they will break? Whats the best way at removing them?

Also I looked around for new elbows and lines I found some grammets I ordered that fit into the top of the valve cover but thats it...i figured id just replace everything if i could instead of cleaning them because the oil is caked inside the lines, didnt find anything....is there some kind of kit anyone sells?

Or where could I get new elbows and lines?
Davers87 is offline   Quote Quick Reply
Old 09-12-2011, 01:56 PM   #15
Jeeper
 
PaulRevere1991's Avatar
 
Join Date: Dec 2009
Location: Port jefferson, NY
Posts: 647
new elbows and lines can be found at the jeep dealer,the elbows you twist and pull.
PaulRevere1991 is offline   Quote Quick Reply
Old 09-12-2011, 02:23 PM   #16
Jeeper

WF Supporting Member
 
jk'n's Avatar
 
Join Date: Jan 2009
Location: First Quadrant in the Land of the Free
Posts: 4,790
I also rock them back and forth if they are difficult.
__________________

Participate in life....Keep movin'....Go there....JK'n it.........Do it! Jeep #1: Red Rock 08 JK Rubicon 4dr, 6 sp manual, Stock Mud Tires, MyGIG Upgrade, Hard Top, after sale BestTop SunRider Soft Top, Congo Cage Rack, Mopar slush mats Jeep #2 Black 08 JK Rubicon 2dr, 6 sp manual, both tops, some chrome...uggg (my wife's jeep) Jeep #3 White 92 YJ (my son's jeep) A great quote from a good friend: "All hail click clack and master jk'n." Click and clack are my idols!
jk'n is offline   Quote Quick Reply
Old 09-12-2011, 03:53 PM   #17
Jeeper
 
Join Date: Aug 2011
Location: Utah
Posts: 88
I stand corrected ... but at least I was on the right track.

__________________
Location: 3 Hours from Little Sahara Dunes
4 Hours from St. Anthony Dunes
4.5 hours from MOAB
DamnBigPapa is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
removing restricter in airbox to increase horsepower beardown YJ Tech Forum 28 02-21-2014 02:04 PM
Why is oil in my airbox 1AGITIS YJ Tech Forum 6 03-01-2011 09:37 AM
Critters In My Airbox dmacioce TJ General Discussion Forum 5 02-02-2011 07:21 AM
A/C and heat airbox for a 97 tj 97tj.jeepinit Classifieds Archive 0 10-21-2009 02:05 PM



Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 09:06 PM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC