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  • Fox 5.0 Mustang Tech

92 5.0 Oil Leak

  • Thread starter Thread starter ZachMorris
  • Start date Start date Aug 13, 2017
Z

ZachMorris

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Jun 21, 2017
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Aug 13, 2017
#1
  • Aug 13, 2017
  • #1
Just had the oil pan gasket changed as it was leaking pretty good...went with felpro molded one piece. Car still has a small drop from inside the bell housing...I'm assuming this is rear main seal ?

The car is a 92 5.0 with a built 306...it's only had about 1000 miles on it in the last 8 years.

Could it be pcv valve ?
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Aug 13, 2017
  • #2
There are several places back there that can leak oil, the rear of the lower intake can be suspect along with the rear main, spray some parts cleaner back there and drive it around for some miles, jack it up and use jack stands, or a lift if you jave access, if you can leave it overnight and use a flashlight to locate the leak.
 
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Z

ZachMorris

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Jun 21, 2017
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#3
  • Aug 13, 2017
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Leak looks like it's coming from inside the bell housing...drips down from there very slowly.

Pulled the pcv valve and its functioning but the mesh screen was very dirty...going to pick up a new one.
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
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Aug 14, 2017
#4
  • Aug 14, 2017
  • #4
If it's coming from inside the bell housing it's more than likely the rear main seal.
 

Ryuk

I love your drawers
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Apr 22, 2017
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Aug 15, 2017
#5
  • Aug 15, 2017
  • #5
Verify that it's not something simple like the back of the intake or valve covers. You'll feel like an idiot if you replace the rear main seal and the problem is still there.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Aug 17, 2017
#6
  • Aug 17, 2017
  • #6
if they didnt put a dab of RTV in the corners when they installed the oil pan gasket, it's going to leak 99% of the time
 

Steel1

Mustang Master
Aug 18, 2017
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#7
  • Aug 18, 2017
  • #7
I was doing some work on my daughters car and had to verify an oil leak. My buddy had bought a leak detection kit for like $50 bucks, came with dye, light and glasses. Made finding the leak easy, might want to give it a try probably get it on Amazon with free shipping.
 
Z

ZachMorris

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Jun 21, 2017
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#8
  • Aug 21, 2017
  • #8
Still fighting this stupid oil leak...cleaned PCV valve and screen, oil pan gasket with new moulded Felpro and I had the Rear Main Seal replaced. Still small drip from the bell housing and the one but beside it...take a look at pictures and let me know thoughts.

I also now have a drip from power steering pump.... joys.
 

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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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polk county florida
Aug 21, 2017
#9
  • Aug 21, 2017
  • #9
I may be a little late, you may have excessive wear where the seal rides on the crank.
Do the flywheel bolts have thread sealer on them?
 
Z

ZachMorris

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  • Aug 21, 2017
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I'm not too sure...the motor is a built 306 with roughly 25k on it. I do see a little wet oil from the back of the valve cover on the drivers side...maybe that's the culprit.

I just bought the car about a month ago...it's had 2100kms put on it in the last 8 years.
 
Z

ZachMorris

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#11
  • Aug 21, 2017
  • #11
I had the rear main and oil pan gasket both done in a shop and they didn't notice any abnormalities although the oil pan gasket definitely needed to be replaced.
 

imp

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Jul 13, 2017
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#12
  • Aug 21, 2017
  • #12
@ZachMorris
I believe there are two oil galleys drilled the length of the engine, which allow interconnection of the valve lifter bores for oil under pressure. They are plugged by driven-in cup-shaped steel plugs. Known to leak, sometimes. imp
 
Z

ZachMorris

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Aug 22, 2017
#13
  • Aug 22, 2017
  • #13
How do I even go about diagnosing either option without pulling the motor?

Fingers crossed its just the valve cover gaskets...but not sure if it would cause the drip at that location.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Aug 22, 2017
#14
  • Aug 22, 2017
  • #14
Oil will run down the path of least resistance, like water, it looks to me to be a rear main leak, watch to see how severe it is. The seal could have been installed dry or too much time between install and start up.
 
Z

ZachMorris

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#15
  • Aug 22, 2017
  • #15
Shop claims they "packed it with grease" regarding the rear main seal and ran it right away.

They said they will de grease the back of the engine and run a few drops of dye and see what they find with their UV light.
 
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Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
909
415
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Greenville, NC
Aug 22, 2017
#16
  • Aug 22, 2017
  • #16
I bet it's the seal. My replacement seal leaked way worse than the original one. I ended up replacing that one with the expensive Felpro Teflon that has to be installed dry. That fixed the issue.
 
Z

ZachMorris

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Aug 22, 2017
#17
  • Aug 22, 2017
  • #17
Fingers crossed its not the seal...I bought it from NAPA and paid for the best one they had lol
 

imp

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Jul 13, 2017
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Aug 22, 2017
#18
  • Aug 22, 2017
  • #18
ZachMorris said:
How do I even go about diagnosing either option without pulling the motor?

Fingers crossed its just the valve cover gaskets...but not sure if it would cause the drip at that location.
Click to expand...
@ZachMorris
Engines invariably are tilted rearward, thus making nearly any leak near the top rear come down the backside. Any leak point between the engine's rear and bellhousing must be accessed with the transmission/housing removed. Eng. need not be removed. imp
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Aug 22, 2017
#19
  • Aug 22, 2017
  • #19
ZachMorris said:
Shop claims they "packed it with grease" regarding the rear main seal and ran it right away.

They said they will de grease the back of the engine and run a few drops of dye and see what they find with their UV light.
Click to expand...

They packed the rear main seal with grease? Serious? You must be mistaken as that is uh......nuts.
You use grease for the pilot bearing
You lightly oil the perimeters of the seal and install it with the spring facing the crank
I normally use the Felpro one with the teflon crank sleeve on anything but a new/refresh build.
If the crank surface is not perfectly round and you dont use the sleeve, chances are it will leak
If you dont install the seal properly and make sure it is not sticking out past the crank flange, it will leak
 
Reactions: imp

imp

Mustang Master
Jul 13, 2017
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Aug 23, 2017
#20
  • Aug 23, 2017
  • #20
mikestang63 said:
They packed the rear main seal with grease? Serious? You must be mistaken as that is uh......nuts.
You use grease for the pilot bearing
You lightly oil the perimeters of the seal and install it with the spring facing the crank
I normally use the Felpro one with the teflon crank sleeve on anything but a new/refresh build.
If the crank surface is not perfectly round and you dont use the sleeve, chances are it will leak
If you dont install the seal properly and make sure it is not sticking out past the crank flange, it will leak
Click to expand...
@mikestang63
Still, admittedly, if you are as old as I am (no one is), and recall the "rope" seals, sliced off with a razor blade after pressing into the main bearing cap and the block, with the prescribed 1/32" excess protruding, ya gotta admit that finally the car engine makers have followed the truck engine e guys, who were years advanced, by using a REAL oil seal, one piece molded in it's own channel, pressed into either the block, or an intermediate seal holder, as was the old Ford Cortina 1.6L and Fiesta 1.6L. I never saw a "leaker" on a Fiesta, owned 4 of them. imp
 
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