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Engine intake manifold oil leak

  • Thread starter Thread starter Enzio
  • Start date Start date Jul 6, 2019
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Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
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Jul 6, 2019
#1
  • Jul 6, 2019
  • #1
I'm back from fishing with another trip planned next weekend.
Busted my butt and got all four KYB shocks installed and this morning finally figured out the source of the tick I could still hear from the engine. (lifters)
I got them straightened out and took the Cobra II out for a spin and I needed gas so I could take it to the custom exhaust guy on Monday. I got on the gas a little getting on the freeway and looked in the rear-view mirror to see the horror happening behind me. Blue smoke bad. I got to the exit ramp two blocks from my house and idled it home. It left an oil trail all the way down my block and into my garage.
The oil was running out the back of the manifold with a nice pool on the block then down the side to land on the headers and exhaust pipes.
I'm discouraged and am going to have a couple of beverages while I ponder getting a new crate engine...
I called and told the exhaust guy we'll need to wait at least a couple of weeks.
I had it running so nice too.
Enzio
 

LILCBRA

I wish I didn't have all of these balls in the air
Mod Dude
Dec 6, 2005
6,347
5,322
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Corn County USA
Jul 7, 2019
#2
  • Jul 7, 2019
  • #2
Assuming you've had the manifold off, did you silicone the connecting points between the cork valley gasket and the actual intake gaskets mated to the head? And you made sure to stick the valley gasket in place before installing the manifold? Iirc, they come with a sticky back with a cellophane or paper backer you remove so the gasket stays in place. Aside from just plain out having a bad gasket, those are usually the 2 main culprits of an oil leak like that. Really not too big of a deal to take care of, especially if that's the case.
 

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
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Jul 7, 2019
#3
  • Jul 7, 2019
  • #3
Hi,
I'm still disgusted but feeling a little better.
Well I used the method described by Edelbrock which uses RTV instead of the gasket. It held for a long time although not many miles. I've ordered a new gasket set from Summit Racing #MS93334 which has the rubber end seals. I'm hoping that is all I need.
I'm kind of amazed that there is that kind of oil pressure in the lifter valley to blow all that oil out. I think I only have a couple of quarts left although I haven't drained it yet. Is there anything else that could cause this? I don't want to go to the effort to replace them only to find out that I should have done a rebuild. Although, it was running great. It was smiles all the way around until I looked in the rear-view mirror. That wiped the smile off my face fast.
Enzio.
 

Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
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#4
  • Jul 7, 2019
  • #4
Which valvecovers are you running?
 

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
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Jul 7, 2019
#5
  • Jul 7, 2019
  • #5
Stock from 1969.
 

2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
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Jul 7, 2019
#6
  • Jul 7, 2019
  • #6
Enzio said:
have a couple of beverages while I ponder getting a new crate engine...
Click to expand...

YES! A brand new Dart 363. I'm there, Heil yeah, Its gonna be Badass! Tires be damned!




Reality = An 5 dollar tube of silicone
If the silicone doesn't fill the void from where the little end gasket is (we all toss that pos), It will do just as you described.
Its just lifter splatter but can empty crankcase fast. Got to fat bead both sides, block and manifold
ask me how I know.
 
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Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#7
  • Jul 7, 2019
  • #7
Reality = An 5 dollar tube of silicone
I'm all about that.
ask me how I know.
I'll bite. How do you know?

My daughter just came over and said she used the same exit off the freeway and followed a trail of oil all the way to my garage. Then she said "Are we having issues?"
 
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2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
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Jul 7, 2019
#8
  • Jul 7, 2019
  • #8
Enzio said:
I'll bite. How do you know?
Click to expand...

I did it recently but didn't want to post about it feeling dumb
Wife followed an oil trail to our driveway stupid manifold end seal anyway.
 
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Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
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Jul 7, 2019
#9
  • Jul 7, 2019
  • #9
Enzio said:
Stock from 1969.
Click to expand...
Two questions, are you running a pcv valve, and are you running a breather on one of them?
 

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
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Jul 7, 2019
#10
  • Jul 7, 2019
  • #10
Yes the same set-up as stock. The PCV valve is newly replaced.
I wish I knew how to do this quote thing.....
 

Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
9,531
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Jul 7, 2019
#11
  • Jul 7, 2019
  • #11
Enzio said:
Yes the same set-up as stock. The PCV valve is newly replaced.
I wish I knew how to do this quote thing.....
Click to expand...
To do a single post, click "reply" on that post. To do more than one, click quote on all of the posts you want to quote, and a button will appear saying "insert quotes", and clicking that will open a dialog box to confirm.
 

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#12
  • Jul 7, 2019
  • #12
74stang2togo said:
To do a single post, click "reply" on that post. To do more than one, click quote on all of the posts you want to quote, and a button will appear saying "insert quotes", and clicking that will open a dialog box to confirm.
Click to expand...
We'll see if this works.
Do you suspect there is something going on other than the fact that I didn't use enough silicone? I am ready to open some more adult beverages if so...
 

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#13
  • Jul 7, 2019
  • #13
2Blue2 said:
I did it recently but didn't want to post about it feeling dumb
Wife followed an oil trail to our driveway stupid manifold end seal anyway.
Click to expand...
I know how you feel. But dumb as it is; I'm not a mechanic so I need to learn and sometimes I look really stupid. It's kinda hard to believe we've both gone down this path.
 
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Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
9,531
5,187
224
Jul 7, 2019
#14
  • Jul 7, 2019
  • #14
Enzio said:
We'll see if this works.
Do you suspect there is something going on other than the fact that I didn't use enough silicone? I am ready to open some more adult beverages if so...
Click to expand...
The four main causes would be excess crankcase pressure, not enough silicone, improper surface prep, or wrong type of silicone (Permatex Ultra Black is best for this job).

If you have a breather and PCV, it's not crankcase pressure.
 
Reactions: Enzio and 2Blue2

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#15
  • Jul 7, 2019
  • #15
Yes I think we're good. I just didn't use enough I guess. What do you think of the rubber seals in the fel pro kit?
 
Last edited by a moderator: Jul 7, 2019

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
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Jul 7, 2019
#16
  • Jul 7, 2019
  • #16
Fwiw- way back when i had my Capri, I came into possession of some barely used aluminum Edelbrock performer heads - Polished Dual plane intake and Endura Shine Carb. Not wanting to bolt these nice parts onto a Ragged out leaky 302, i plucked a prime candidate from an F150 .. The new engine got Bored cylinders - Polished Crank - Fresh pistons etc. took a summers worth of bagging grocery's and mowing lawns to put together, all for installing shiny heads and an intake. once it was all assembled and set in the car, I installed the intake - against my dad's advice, without silicon, cause i didn't want rtv spooging out all over my freshly painted engine and my Super pretty intake lol. And it leaked like crazy-from the front of the intake, and the rear . Oil everywhere. To add to my hard headedness-I tried two more times with two different types of intake gaskets (which also leaked) before finally gluing the intake at the china walls with the ritestuff rtv.. Never leaked again (from the intake anyways, other areas i didn't use rtv started seeping eventually :-( .)
 
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Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#17
  • Jul 7, 2019
  • #17
Okay you moderators need to get together... Should I use Ultra Black or Ritestuff?
 

LILCBRA

I wish I didn't have all of these balls in the air
Mod Dude
Dec 6, 2005
6,347
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Corn County USA
Jul 7, 2019
#18
  • Jul 7, 2019
  • #18
Ultra Black is what I've used. And the rubber gasket is preferred over the cork. Paste it down to the block, apply a bead to the top of the rubber gasket and a little extra dab at the intersections and you should be good. If you have extra crankcase pressure from bad rings or anything that caused that leak, you'll find another weak point soon. I ran into the issue with my 302 which is one of the reasons for my tear down a few years ago. I found I had a broken compression ring so oil was finding it's way out at any weak point it could including my breather. I went so far at one point before finally giving in and tearing it down as to change from the rubber oil pan gasket that was in it back to a cork gasket while the engine was still in the car. I thought maybe I had torn or slipped the rubber gasket which was the problem, but I found out soon after that it was indeed crankcase pressure necessitating the tear down. In my case it really wasn't that big of a deal. I ran my cylinder hone through the scratched cylinder and was able to keep it from going too far out of tolerance while giving the cylinder it's crosshatch pattern. I don't think I'd recommend someone do that without proper tools and all that, but it CAN be done.

Before I went back to school again I was a journeyman toolmaker and I have a set of dial bore gauges with a .0001" indicator, I was able to keep a very close eye on what I was doing. But for someone inexperienced, I'd suggest taking the block somewhere to have the work done if they were to run into anything similar.
 
Reactions: Enzio

Enzio

Dang it. I was hoping mine would get 3 more inches
5 Year Member
May 14, 2019
1,054
840
133
Minnesota
Jul 7, 2019
#19
  • Jul 7, 2019
  • #19
LILCBRA said:
Ultra Black is what I've used. And the rubber gasket is preferred over the cork. Paste it down to the block, apply a bead to the top of the rubber gasket and a little extra dab at the intersections and you should be good. If you have extra crankcase pressure from bad rings or anything that caused that leak, you'll find another weak point soon. I ran into the issue with my 302 which is one of the reasons for my tear down a few years ago. I found I had a broken compression ring so oil was finding it's way out at any weak point it could including my breather. I went so far at one point before finally giving in and tearing it down as to change from the rubber oil pan gasket that was in it back to a cork gasket while the engine was still in the car. I thought maybe I had torn or slipped the rubber gasket which was the problem, but I found out soon after that it was indeed crankcase pressure necessitating the tear down. In my case it really wasn't that big of a deal. I ran my cylinder hone through the scratched cylinder and was able to keep it from going too far out of tolerance while giving the cylinder it's crosshatch pattern. I don't think I'd recommend someone do that without proper tools and all that, but it CAN be done.

Before I went back to school again I was a journeyman toolmaker and I have a set of dial bore gauges with a .0001" indicator, I was able to keep a very close eye on what I was doing. But for someone inexperienced, I'd suggest taking the block somewhere to have the work done if they were to run into anything similar.
Click to expand...

I'm following this. If the end seal starts to leak and I get it sealed then I'm looking for the oil pan gaskets to see if they suddenly start to leak and I may have the same problem. Great advice. I'll update. Thank you very much.
Enzio
 
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Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
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Jul 7, 2019
#20
  • Jul 7, 2019
  • #20
Enzio said:
Yes I think we're good. I just didn't use enough I guess. What do you think of the rubber seals in the fel pro kit?
Click to expand...
I don't use end seals at all, just a 1/4" to 3/8" bead of Ultra Black.
 
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