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5.0 leaking out oil

  • Thread starter Thread starter SmokeytheFox
  • Start date Start date Jul 27, 2020
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SmokeytheFox

5 Year Member
Jul 19, 2018
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3
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Cleveland,Ohio
Jul 27, 2020
#1
  • Jul 27, 2020
  • #1
For the past few days I’ve been trying to figure out where this leak is coming from. When I start the car cold no oil drips out. After about 15 minutes of warming up, oil comes running out the backside of the engine while running. Could this be a rear main seal or oil pan gasket? Is it common for it to leak this BAD ? Pic is from a video. Car is basically undriveable because of the leak.
 

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Steel1

Mustang Master
Aug 18, 2017
1,419
639
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Connecticut
Jul 27, 2020
#2
  • Jul 27, 2020
  • #2
Probably rear main or back of the lower intake, you're going to need to do some investigating.
Both areas a fairly common for oil leaks.
 

SmokeytheFox

5 Year Member
Jul 19, 2018
24
3
13
Cleveland,Ohio
Jul 27, 2020
#3
  • Jul 27, 2020
  • #3
Steel1 said:
Probably rear main or back of the lower intake, you're going to need to do some investigating.
Both areas a fairly common for oil leaks.
Click to expand...
Back of the intake and bell housing is bone dry
 

Steel1

Mustang Master
Aug 18, 2017
1,419
639
143
Connecticut
Jul 27, 2020
#4
  • Jul 27, 2020
  • #4
SmokeytheFox said:
Back of the intake and bell housing is bone dry
Click to expand...
Signs point to rear main, transmission needs to come out for replacement might want to replace pilot bearing while
you're in there.
 
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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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#5
  • Jul 27, 2020
  • #5
I agree, but I will ad if the car has a lot of miles I would pick up a crank repair sleeve and seal.
I've also heard about the flywheel bolts needing thread sealant because oil can seep through the threads but I personally use thread locker on them and have never encountered that problem. Just thought I'd mention it.
 
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SmokeytheFox

5 Year Member
Jul 19, 2018
24
3
13
Cleveland,Ohio
Jul 27, 2020
#6
  • Jul 27, 2020
  • #6
General karthief said:
I agree, but I will ad if the car has a lot of miles I would pick up a crank repair sleeve and seal.
I've also heard about the flywheel bolts needing thread sealant because oil can seep through the threads but I personally use thread locker on them and have never encountered that problem. Just thought I'd mention it.
Click to expand...
Previous owner claimed it was “rebuilt” but who knows what that means lol. Is it ok to add the sleeve even if the crank has no groove mark in it ?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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#7
  • Jul 27, 2020
  • #7
Yes, the sleeve will come with a seal.
Or at least it should.
 
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,233
17,919
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Massachusetts
Jul 28, 2020
#8
  • Jul 28, 2020
  • #8
General karthief said:
Yes, the sleeve will come with a seal.
Or at least it should.
Click to expand...

It's a separate purchase. Felpro makes a sleeve, and an install tool. With the tool, it was very easy to put on. I then returned it as it looked new.


It was tough to see the groove on my crankshaft, but with the light held the right way, you could see it. Engine only had 100k miles on it as well.
 
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Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Jul 28, 2020
#9
  • Jul 28, 2020
  • #9
I've seen both kits. I once had to buy a sleeve kit in order to get the seal because the place I was at didn't have the seal in-stock. LoL

This was at an O'Reilies.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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#10
  • Jul 28, 2020
  • #10
It is annoying how very little wear can cause a big leak. Yes, the sleeve is fine even without a noticeable wear ring. The seal will just fit a little tighter with the thin sleeve, and any new wear will be on the replaceable sleeve.

I had to have a machine shop make a sleeve for a rarer pinion shaft that the catalog missed for size. Not seating the seal quite all the way in just made another ring that leaked again. The machine shop’s repair sleeve dried up that differential and was not as expensive as a salvage yard part that probably also needed fixed. The pre made ones are a slick deal and worth a try.

SmokeytheFox said:
Previous owner claimed it was “rebuilt” but who knows what that means lol. Is it ok to add the sleeve even if the crank has no groove mark in it ?
Click to expand...
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
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164
Palm Beach Gardens, FL
Jul 28, 2020
#11
  • Jul 28, 2020
  • #11
Looks like the oil pan gasket to me.
 
B

Bird76Mojo

5 Year Member
Jul 12, 2018
66
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Aug 1, 2020
#12
  • Aug 1, 2020
  • #12
Don't sleeve the crank until it's your last resort. Get an offset-lip rear main seal first.

Here's what I used: http://rover.ebay.com/rover/1/711-5...0001&campid=5335821607&icep_item=173115399719
 

General karthief

wonder how much it would cost to ship you a pair
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#13
  • Aug 1, 2020
  • #13
Bird76Mojo said:
Don't sleeve the crank until it's your last resort. Get an offset-lip rear main seal first.

Here's what I used: http://rover.ebay.com/rover/1/711-5...0001&campid=5335821607&icep_item=173115399719
Click to expand...
I did not see anything about this being an 'offset' seal. Nothing in the link or the part number from the manufacturer.
And why would a sleeve be a last resort? Just curious.
 
B

Bird76Mojo

5 Year Member
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Aug 8, 2020
#14
  • Aug 8, 2020
  • #14
General karthief said:
I did not see anything about this being an 'offset' seal. Nothing in the link or the part number from the manufacturer.
And why would a sleeve be a last resort? Just curious.
Click to expand...

Says it all right here. Took 10 seconds on Google. OFFSET DOUBLE LIP REAR MAIN SEAL.

More Information for ENGINETECH S4686


I personally sleeve cranks as a last resort because there's really no going back to an offset seal. If you go offset seal first, then still have problems, then you can sleeve the crank. The point is you get more than one try at it..
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
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#15
  • Aug 8, 2020
  • #15
If you hit the link that was posted there is nothing (that I read) that mentioned the seal being offset. Same when I googled the part number.
And why would you 'go back'?
 

7991LXnSHO

wanna catch the space herp
10 Year Member
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#16
  • Aug 9, 2020
  • #16
I’m ready to learn something today. Why will an offset seal not wrk with a quick sleeve???? The Felpro Counter Pro certification never mentioned anything about that.

Bird76Mojo said:
Says it all right here. Took 10 seconds on Google. OFFSET DOUBLE LIP REAR MAIN SEAL.

More Information for ENGINETECH S4686


I personally sleeve cranks as a last resort because there's really no going back to an offset seal. If you go offset seal first, then still have problems, then you can sleeve the crank. The point is you get more than one try at it..
Click to expand...
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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Jan 4, 1985
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#17
  • Aug 9, 2020
  • #17
General karthief said:
I did not see anything about this being an 'offset' seal. Nothing in the link or the part number from the manufacturer.
And why would a sleeve be a last resort? Just curious.
Click to expand...





7991LXnSHO said:
Why will an offset seal not wrk with a quick sleeve????
Click to expand...


...and this although, I'm not sure why you would need an offset seal and quick sleeve.

and finally this:

General karthief said:
why would you 'go back'?
Click to expand...


I dunno why either.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
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Aug 9, 2020
#18
  • Aug 9, 2020
  • #18
@Bird76Mojo says the sleeve is the last resort because there is really no going back to an offset seal. Why? If your sleeve gets a ring, why would an offset seal not still work? I would probably replace the sleeve, but they are not supposed to be thick enough to be a problem with a viton seal.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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Aug 9, 2020
#19
  • Aug 9, 2020
  • #19
If you hit the link in post #12 the page that comes up from ebay says nothing about it being an offset anything. That's all. Not a big deal, I had not heard of one, so this debate can end.
And I'm sure a repair sleeve can be removed, not that you would ever need to, if you doubt it just send me a crankshaft with a repair sleeve on it and I will show you how.
 

Noobz347

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#20
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  • #20
I always considered replacing the crank to be the second to last resort followed by the engine.
 
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