Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by:
Sponsored by: CARiD

Oil on air filter causes?!?!

Thread Tools
 
Search this Thread
 
Old Sep 7, 2011 | 12:12 PM
  #1  
trevorsmith82's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2011
Posts: 68
Likes: 0
From: Atlanta, Ga
Car: 82 Firebird/ 79 Camaro Berlinetta
Engine: 151 Pontiac Iron Duke TBI/ 305 SBC
Transmission: THM200/ THM200r4
Axle/Gears: 2.93/ 2.41
Oil on air filter causes?!?!

Today checking my oil air filter etc, I came across oil blow back on my air filter, only on the side where the air filter breather is. I know its coming through the air breather is, I just need to know whats causing this and should I be concerned.

Engine btw is a 2.5 iron duke I know its shameful
Reply
Old Sep 7, 2011 | 12:23 PM
  #2  
Apeiron's Avatar
Moderator
 
Joined: Jan 2000
Posts: 20,981
Likes: 11
From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: Oil on air filter causes?!?!

Excess crankcase pressure and/or bad PCV.
Reply
Old Sep 7, 2011 | 12:25 PM
  #3  
trevorsmith82's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2011
Posts: 68
Likes: 0
From: Atlanta, Ga
Car: 82 Firebird/ 79 Camaro Berlinetta
Engine: 151 Pontiac Iron Duke TBI/ 305 SBC
Transmission: THM200/ THM200r4
Axle/Gears: 2.93/ 2.41
Re: Oil on air filter causes?!?!

Originally Posted by Apeiron
Excess crankcase pressure and/or bad PCV.
PCV was replaced recently though it might be a dud, how would i deal with the excess crankcase pressure if that was cause?

thanks
Reply
Old Sep 8, 2011 | 05:57 PM
  #4  
Damon's Avatar
Supreme Member
 
Joined: Sep 1999
Posts: 7,072
Likes: 13
From: Philly, PA
Re: Oil on air filter causes?!?!

It's the PCV system almost certainly (otherwise the rings are shot and it's rebuild time).

Pop the PCV out of the valve cover with the engine idling. See if it's got strong vacuum at the end of the PCV valve where the hole is (it should). While you're at it, see how much blow by is drifting out of the PCV hole in the valve cover. If it's chuggign like an old freight train, the rings are shot and you're all done. Hopefully that's not the case.

Sometimes the PCV valve is fine but the line connecting it to the intake is plugged up with decades old oil schmutz. Old Pontiac V8s were famous for this. Maybe the Iron Duke as well? Worth checking anyway. That includes checking the PCV hose nipple on the intake/carb as well. When they plug up like that it's usually about everything that plugs up!
Reply
Old Sep 10, 2011 | 12:29 PM
  #5  
trevorsmith82's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2011
Posts: 68
Likes: 0
From: Atlanta, Ga
Car: 82 Firebird/ 79 Camaro Berlinetta
Engine: 151 Pontiac Iron Duke TBI/ 305 SBC
Transmission: THM200/ THM200r4
Axle/Gears: 2.93/ 2.41
Re: Oil on air filter causes?!?!

Originally Posted by Damon
It's the PCV system almost certainly (otherwise the rings are shot and it's rebuild time).

Pop the PCV out of the valve cover with the engine idling. See if it's got strong vacuum at the end of the PCV valve where the hole is (it should). While you're at it, see how much blow by is drifting out of the PCV hole in the valve cover. If it's chuggign like an old freight train, the rings are shot and you're all done. Hopefully that's not the case.

Sometimes the PCV valve is fine but the line connecting it to the intake is plugged up with decades old oil schmutz. Old Pontiac V8s were famous for this. Maybe the Iron Duke as well? Worth checking anyway. That includes checking the PCV hose nipple on the intake/carb as well. When they plug up like that it's usually about everything that plugs up!
I dont think its rebuild time, this engine only has 64,000 miles on it unless letting and car and engine sit for period time can cause rings to go bad. Its only soaking the air filter on the side where the air breather connects to the air cleaner.
Ill do the test you instructed and see whats going on here thank you!
Reply
Old Apr 21, 2012 | 05:59 PM
  #6  
punkmaster98's Avatar
Supreme Member
10 Year Member
Liked
Loved
Community Favorite
iTrader: (5)
 
Joined: Aug 2011
Posts: 1,261
Likes: 196
From: Jackson NJ
Car: 1984 T/A
Engine: LQ4
Transmission: T56
Axle/Gears: Ford 8.8 4.10 gears
Re: Oil on air filter causes?!?!

Im having the same problem. ill try that too.
Reply
Old Apr 22, 2012 | 01:10 PM
  #7  
hondorian7's Avatar
Junior Member
 
Joined: Sep 2009
Posts: 19
Likes: 0
From: Minnesota
Car: 91 Chevy Camaro RS
Engine: 305 TBI
Transmission: 700R4
Re: Oil on air filter causes?!?!

i had this problem and if its TBI take of the TBI and check where the pcv line goes in. mine was mostly clogged not getting enough vaccum but did have some. after i cleaned it good and attached everything back up i put a breather tube on the valve cover going to the air filter and havent had any problems or oil in the filter since then. you dont need the breather but i wanted to put it on to help with oil on filter.
Reply
Old Apr 23, 2012 | 09:33 PM
  #8  
trevorsmith82's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2011
Posts: 68
Likes: 0
From: Atlanta, Ga
Car: 82 Firebird/ 79 Camaro Berlinetta
Engine: 151 Pontiac Iron Duke TBI/ 305 SBC
Transmission: THM200/ THM200r4
Axle/Gears: 2.93/ 2.41
Re: Oil on air filter causes?!?!

Ive done so many things to the engine since my last post
I did a compression check and the rings check out fine
I went through rebuilt the throttle body installed a new pcv valve with a catch can
And I hate to say it still blows oil
It has so much pressure in there it like to pop out my pcv valve and blow oil through my valve cover gasket
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
eightsixseven
Tech / General Engine
2
Dec 16, 2024 01:50 PM
1992 Trans Am
History / Originality
27
May 10, 2023 07:19 PM
Brinkkl2000
Tech / General Engine
5
Aug 4, 2018 08:29 AM
Derick15
Tech / General Engine
2
Sep 17, 2016 05:28 PM
Zachattack0925
Transmissions and Drivetrain
4
Aug 12, 2015 09:52 PM




All times are GMT -5. The time now is 04:18 PM.