Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: Trevla on July 26, 2005, 03:24:03 PM

Title: 5.0 oil leaks on top of intake maniflod
Post by: Trevla on July 26, 2005, 03:24:03 PM
86 T-Bird 5.0  with AC AOD
I have some oil leaks on my 5.0
Knowing part of the problem was the valve cover gaskets I took off the upper intake manifold to remove the valve covers and found a large puddle of oil sitting on top of the lower intake manifold.

Looking underneath the upper intake manifold I found an unknown part sitting loose in the manifold leaking oil.
Is this the cause of my puddle and if so how do I seal it correctly?
Teflon tape, gasket sealer, O-ring?



The car came with after market valve covers and the old valve cover breather was just laying in between the two manifolds.
Is this ok or should I do something else with it?


If these repairs do not solve all my oil leaks how hard is it to pull the whole engine out and put it back in?
I have done engine swaps before. Mostly Chevy’s and carburated cars.
This would be my first computered control engine, way to many wires for me.
I have a Haynes shop manual to go by.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: TurboCoupe50 on July 26, 2005, 04:51:05 PM
The PCV(#2) should be in the rear of the lower intake(I'm assuming it was just laying on the intake). Without it the crankcase will build up pressure and seep oil. Also the wire mesh seperator(also in the rear of the intake) should be checked to be sure it isn't caked with sludge, which is another common problem...
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: Trevla on August 24, 2005, 10:11:45 PM
OK update time
I ended up pulling the engine out (oh what a joy to many wires for my liking), I took pics of every thing as I took it apart.
The intake was leaking on 3 sides, timing chain cover was leaking, and the oil pan was fine.

 Pic 1
The wire mesh was packed solid.
Is there a way to take out the inner wire mesh (looks like an SOS pad)?
I soaked the intake in parts cleaner and it is still clogged up. I can fill the hole with cleaner and it does not drain through.

Pic 2 and 3
The intake looked like it was leaking between the intake and the head.
There is a hole on the heads that the old and the new gaskets do not cover up.
Is there something I can do to fix this or is that just the way it is?
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: 5.0willgo on August 24, 2005, 10:23:02 PM
The mesh sits inside a metal case thing that is pushed into that location of the lower manifold. Get a pair of needle nose pliers and pull it out. Either grab it from one of those metal tabs from the top or push it through the top from the bottom with a screwdriver.
You could go ahead and replace it. They aren't expensive. Usually spray it with carb cleaner which should soak through and clean the oil buildup out but if it's still clogged just replace it.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: slicksport88 on August 24, 2005, 10:28:11 PM
I just did the same thing your doing a few months back. Your better off replacing the wire mesh filter. Mine was packed solid and impossible to clean. Only paid like 3 or 4 bucks from the dealer for one. As far as your intake goes...i took my upper and lower to a machine shop to have em dipped. Did a beautiful job in the end. And I don't recognize that upper hole...don't remember seeing that on my heads.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: Trevla on August 24, 2005, 10:36:18 PM
Ok I got the mesh out had to push it out from inside.
Is there a proper part name to ask for?


The hole is a small chamber underneth the valve cover bolt hole
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: nirvanagod on August 24, 2005, 11:31:05 PM
http://www.foxtbirdcougarforums.com/showthread.php?t=3206&page=2&pp=10&highlight=pcv+valve

About halfway down or so there's a pic of the part, old and new. It's technically called the "Crankcase Filter". The box in the pic has the part # on it for Motorcraft branded piece.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: TurboCoupe50 on August 25, 2005, 01:00:09 AM
I can't say as I remember the holes in the heads... Are they drilled into the valve cover area???
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: Trevla on August 25, 2005, 06:42:26 AM
Are they drilled into the valve cover area???

no but the bolt hole above does go into it

I was thinking maybe since the crankcase filter was clogged
that maybe the intake gasket failed over time at that spot.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: vinnietbird on August 25, 2005, 09:05:13 AM
My heads have the holes in them like that.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: Trevla on September 07, 2005, 09:35:42 PM
Thanks for all the help and for the link nirvana god
I have the engine back in the car and came across (hopefully) one last problem.

I can’t get the throttle cable bracket back on right.
The bracket now hits the valve cover and I can’t align the lower hole.
The bracket fit before and is not bent out of shape.
I have cork valve cover gaskets about 1/8 inch high
There are 2 other holes drilled in the bracket but not big enough for the bolts.
To me it looks like someone else had the same problem.
Any clues as what to do?
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: TurboCoupe50 on September 09, 2005, 02:16:29 PM
It should just bolt on....

(http://www.members.pen 15s.net/mr428/P4090120.JPG)
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: vinnietbird on September 09, 2005, 06:35:47 PM
I had that problem with a set of valve covers I was using.I took the Throttle cable bracket and drilled the holes in an oval so I could move the bracket up enough to clear the valve covers.No problems after that.Some valve covers (standard height) are taller than the factory 5.0 covers.It's a very quick and easy fix that won't harm your car,and you can just move it down if you go back to stock covers.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: thunderjet302 on September 11, 2005, 10:43:45 PM
I have tall chrome valve covers and they hit the bracket. I ended up using a FMS 1/2" upper intake spacer to gain clearance.
Title: Re: 5.0 oil leaks on top of intake maniflod
Post by: thunderjet302 on September 11, 2005, 10:44:29 PM
Btw engine looks real good.