5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.

Oil in upper intake?

Thread Tools
 
Search this Thread
 
Old Dec 15, 2011 | 05:51 PM
  #1  
Project 5.GO!'s Avatar
Project 5.GO!
Thread Starter
2nd Gear Member
 
Joined: May 2008
Posts: 478
From: Florida
Default Oil in upper intake?

A problem I have been having for a couple years, even after an engine rebuild is the car using oil and it never being explained. I accidentally found out where it has been going when I opened the side port on my Performer upper intake to repaint it. There was a small pool of oil at the bottom inside. Somehow it has been sneaking in there, and it isnt through the hose that connects the oil fill tube to the throttle body (its clean).

I asked a guy at Discount when I was there today and he told me it was a PCV valve that was gummed up, but he called a mechanic he knows, and the mechanic said that there is too much bottom end pressure, which is blowing the oil up there.

Back when I did the rebuild, I took off the smog system, and the original heads had a metal pressure equalizer tube that connected the two, but since the GT40 heads didnt have the ports, I didn't put the tube back in.

I will be replacing the PCV valve again (even though I did it about 12k miles ago, at the rebuild), and pulling the screen and cleaning it. Is there anything else I should be doing to prevent this?
Old Dec 15, 2011 | 07:00 PM
  #2  
mattkoly's Avatar
mattkoly
2nd Gear Member
 
Joined: Jan 2006
Posts: 384
From: Colorado
Default

I had the exact problem with my edelbrock manifold...

The lower intake under the hole where the pcv goes there should be a baffle or piece of sheet metal (NOT THE SCREEN OR SPONGE). Pull the pcv, screen, and spong and put finger in hole. If no baffle, that's ur problem. They are supposed to be installed by mechanic and are commonly overlooked

I'll try to find pix...
Old Dec 15, 2011 | 07:10 PM
  #3  
mattkoly's Avatar
mattkoly
2nd Gear Member
 
Joined: Jan 2006
Posts: 384
From: Colorado
Default

See step 25 of assembly on this page...

http://www.fordmuscle.com/archives/2...tor/index4.php

Hope this helps.
Old Dec 15, 2011 | 08:26 PM
  #4  
Project 5.GO!'s Avatar
Project 5.GO!
Thread Starter
2nd Gear Member
 
Joined: May 2008
Posts: 478
From: Florida
Default

I distinctly remember that baffle being on the intake when I installed it. I got the intake combo used, and I remember cleaning heavy oil residue out of everything and reassembling it. The baffle is definitely there, which is why im so confused. Is it possible that because there is no equalizer tube between the heads that there is too much pressure that needs a place to go?

Would it mess things up if I let the PCV vent into open air or a collector box instead of the intake? Maybe if I could put a collector box in the line between the PCV and intake, it would at least keep the oil out of the intake. I imagine the oil is either getting sucked into the vacuum lines or dropping into the combustion chamber. Either way, it isnt necessarily a good thing...
Old Dec 15, 2011 | 08:43 PM
  #5  
mattkoly's Avatar
mattkoly
2nd Gear Member
 
Joined: Jan 2006
Posts: 384
From: Colorado
Default

Are u talking about the tone on the back of the heads? If so, I think that is for emissions.
Old Dec 15, 2011 | 09:10 PM
  #6  
Project 5.GO!'s Avatar
Project 5.GO!
Thread Starter
2nd Gear Member
 
Joined: May 2008
Posts: 478
From: Florida
Default

Yep. I was thinking that even if it was emissions, it was still venting pressure.
Old Dec 16, 2011 | 06:00 AM
  #7  
mattdel's Avatar
mattdel
6th Gear Member
 
Joined: Nov 2006
Posts: 9,239
From: Spfld, MA
Default

Excessive oil pooling in the intake is because you're actually creating a vacuum inside the block instead of just a nice steady vent. If you go with some aftermarket valve covers that have breather filters on them, it should clear up the problem.
Old Dec 16, 2011 | 10:38 AM
  #8  
Project 5.GO!'s Avatar
Project 5.GO!
Thread Starter
2nd Gear Member
 
Joined: May 2008
Posts: 478
From: Florida
Default

Looking at Edelbrock vented covers, and I see they have breather holes, but no fill neck. Am I supposed to remove the filter and pour new oil through the hole? I'm assuming I wouldnt need the tube that goes between the filler neck and throttle body because they are vented.
Old Dec 17, 2011 | 08:23 PM
  #9  
decipha's Avatar
decipha
2nd Gear Member
 
Joined: Jul 2006
Posts: 315
From: Louisiana
Default

you want the crankcase under vaccum, do not run an open breather, remove the screen in the back of the intake under the pcv, install a catch can

/enjoy
Old Dec 17, 2011 | 08:44 PM
  #10  
Project 5.GO!'s Avatar
Project 5.GO!
Thread Starter
2nd Gear Member
 
Joined: May 2008
Posts: 478
From: Florida
Default

Why would I remove the screen, won't that let more oil pass to the catch can? Thanks for the reply!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
EASTIDEE123
5.0L (1979-1995) Mustang
14
Sep 14, 2015 03:52 PM
Scottyboy187
SVT Forums
1
Sep 13, 2015 10:23 PM
MusicCity615
General Tech
7
Sep 12, 2015 07:05 AM
angeljoelv
SVT Forums
0
Sep 10, 2015 09:12 PM
kevsgt
GT S197 General Discussion
1
Sep 9, 2015 06:20 AM




All times are GMT -5. The time now is 06:27 PM.