4.6L (1996-2004 Modular) Mustang Technical discussions on 1996-2004 4.6 Liter Modular Motors (2V and 4V) within.

New Built motor leaking massive amounts of oil..

Old 10-23-2009, 03:25 PM
  #1  
Blk003GT
4th Gear Member
Thread Starter
 
Blk003GT's Avatar
 
Join Date: Apr 2008
Location: mi
Posts: 1,087
Default New Built motor leaking massive amounts of oil..

My motor has about 3500 miles on it, its a built short block and when they built it they dissaembled the heads and cleaned them and everything. about a month or so ago it started smoking and noticed oil on the pass. valve cover and thinking it was the seals in the supercharger going bad i was going to have it rebuilt. but after looking at the charge pipes its not comming from the supercharger.

within the last week it has been smoking really really bad. i say smoking because oil is leaking onto the headers its NOT comming out the exhaust pipe. i have been checking the oil regularly and adding when need be while trying to figure out where it is comming from. the oil on the top of the motor is ONLY on the pass side valve cover and around the back of the motor on the pass. side. under the car its EVERYWHERE, its dripping in oil. the car sat for about 1min after driving about 3 miles today and there was a puddle of oil underneith it about 6in x 6in. its like pouring out.

i thought previously it might be a valve cover gasket but would that cause that much oil to leak out. i just don't know where else to look.
Blk003GT is offline  
Old 10-23-2009, 04:41 PM
  #2  
masterofthepuppets99
2nd Gear Member
 
masterofthepuppets99's Avatar
 
Join Date: Feb 2009
Location: Portland, Oregon
Posts: 324
Default

dont quote me on this, but somewhere i read that the passenger head is different from the driver side head. if they are mixed up a leak will spring from the backside of the passenger side head. i think its an oil passage. i really cant remember honestly. im sure someone will chime in. good luck
masterofthepuppets99 is offline  
Old 10-23-2009, 05:03 PM
  #3  
Tim99GT
4th Gear Member
 
Tim99GT's Avatar
 
Join Date: Dec 2007
Location: Lafayette, LA
Posts: 1,700
Default

Well the heads are identical, but they can be mismatched. On the back side of the heads there are ports. I believe the pass side has to be plugged off. I think... I will try and look tonight. I remember oxford telling me this a long time ago. One of the heads have to be plugged and the other has to be open. I will look for the thread.
Tim99GT is offline  
Old 10-23-2009, 05:20 PM
  #4  
wolverine8490
3rd Gear Member
 
wolverine8490's Avatar
 
Join Date: May 2007
Location: OH
Posts: 564
Default

A leaking valve cover gasket can cause one heck of a leak. Check that, Oil pressure guage (dont know its location off the top of my head), and also the PCV. It should not be to hard to find the source of the leak. A shop shoul dbe able to add dye to the oil as well and find your leak pretty fast.
wolverine8490 is offline  
Old 10-23-2009, 06:03 PM
  #5  
dimebag
6th Gear Member
 
dimebag's Avatar
 
Join Date: May 2006
Location: earleville md
Posts: 10,357
Default

I have both heads off of my car right now, ill give it a look tm morning. The tensioners are bolted onto the heads, and work off of oil pressure. Its possible they took the plugs out of the back of the heads to clean em out and didn't put them back, or not properly.like I said I have both heads off right now, ill see where the possible leak could be coming from tom morning
dimebag is offline  
Old 10-23-2009, 07:12 PM
  #6  
Blk003GT
4th Gear Member
Thread Starter
 
Blk003GT's Avatar
 
Join Date: Apr 2008
Location: mi
Posts: 1,087
Default

alright thanks. thinking it was the pcv i caped off the tube on the throttle body and put a breather on the pcv but no change. where it acutally leaks from underneigh the car seems to be right smack dab in the middle of the car but then again the whole under side is covered in oil. but that does sound like the head issue could be it becuase it is ONLY leaking from the pass. side. i also checked to make sure the valve cover bolts were tight and they where.

should i go thru all the trouble and try too do a valve cover gasket or should i investigate more. when i looked last time it looked like there was drips comming from the head and running down the headers but then again it dosen't explain why the leak seems to be comming from more the middle area were it acutally drips down under the car and also why the underside it coated from the very front of the motor to the very back of the motor.

could it maybe be a rear main seal? i don't know if that would leak that much oil tho.

i made an appt. with the shop but its not until thursday so if i can figure it out b4 then i'm gunna try to do that.
Blk003GT is offline  
Old 10-23-2009, 08:04 PM
  #7  
massred98gt
2nd Gear Member
 
massred98gt's Avatar
 
Join Date: Oct 2008
Location: massachussets
Posts: 467
Default

dude if it was a oil galley plug that they forgot to unplug you would lose oil pressure within the first 30 secs the car is running. ask me how i know lol. i missed a bung in the front of my passenger head when i swaped heads. live and learn. if its leaking as much as u said it is then you should be able to find the source of the leak no problem!!! fill her up with oil start it up and pop the hood or jack it up and get ur AS# underneath to locate the leak. regardless, its the shops fault and they should fix the prob for free. how hard have u been beating the car since the install? Cracked block? don't know just throughin out options
massred98gt is offline  
Old 10-23-2009, 08:18 PM
  #8  
xtexsol37
 
xtexsol37's Avatar
 
Join Date: Sep 2009
Location: Michigan
Posts: 15
Default

DO you have a block breather other than on the valve covers. it sounds like that you are create a lot of pressure in the block and the oil is just leaking from the weakest point. I had a supercharger and I blew the rear main seal, head gaskets and my spacer was always wet on the pass side after driving because I could not releave the pressure fast enough so oil was blowing up into the intake. I had a block breather hooked up to both valve covers connected with 10an lines and still had a problem.
xtexsol37 is offline  
Old 10-23-2009, 08:20 PM
  #9  
xtexsol37
 
xtexsol37's Avatar
 
Join Date: Sep 2009
Location: Michigan
Posts: 15
Default

with a supercharger check and make sure you didn't blow the pcv valve out of the intake.
xtexsol37 is offline  
Old 10-23-2009, 10:29 PM
  #10  
Tim99GT
4th Gear Member
 
Tim99GT's Avatar
 
Join Date: Dec 2007
Location: Lafayette, LA
Posts: 1,700
Default

Here s the thread i was talking about:
https://mustangforums.com/forum/4-6-...-help-plz.html

Its the drivers side head that has to be plugged. Sorry, i had it backwards.

Last edited by Tim99GT; 10-23-2009 at 10:34 PM.
Tim99GT is offline  

Thread Tools
Search this Thread
Quick Reply: New Built motor leaking massive amounts of oil..



All times are GMT -5. The time now is 07:20 AM.