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Rear main seal leak? *DUW*

  • Thread starter Thread starter BlackVert
  • Start date Start date Oct 7, 2006
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BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 7, 2006
#1
  • Oct 7, 2006
  • #1
Is this evidence of a rear main seal leak?











 

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1TallMF

New Member
Apr 17, 2006
955
1
0
Montreal
Oct 7, 2006
#2
  • Oct 7, 2006
  • #2
Thats a deffinate YES. That sucks dude
 

JJ95GTID

Active Member
Sep 22, 2003
1,141
4
49
Phoenix, AZ
Oct 7, 2006
#3
  • Oct 7, 2006
  • #3
It may not be. When I pulled the intake off last time I found the gaskets I used split in half and leaked oil out the back. I thought for the longest time I had a rear main seal leak. When I reinstalled the intake I used a thick bead of silicon instead of the supplied gaskets and the leak went away. All that nasty oil around the flywheel pan cleaned up after a couple months.
 

1TallMF

New Member
Apr 17, 2006
955
1
0
Montreal
Oct 7, 2006
#4
  • Oct 7, 2006
  • #4
Good point. He'd have to have a look at the top of the bellhousing to see if its full of oil there, but it looks to me that its coming from a spot exactly the size of the RMS, and it doesn't look like its running down the sides of the bellhousing.
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
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Bethesda, MD
Oct 7, 2006
#5
  • Oct 7, 2006
  • #5
ok more pics coming ...
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 7, 2006
#6
  • Oct 7, 2006
  • #6
now i'm thinking it might be from cylinder #8 ... i just got the header off















 

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blksn955.o

Founding Member
Mar 15, 2002
3,263
0
66
st.louis mo 314
Oct 7, 2006
#7
  • Oct 7, 2006
  • #7
damn, I would almost say the whole pan gasket. But I would almost say like 90% rear main, and the rest other stuff from the looks.

What was the oil pres.?

Mine has a slight rear main leak (just alittle haze right at the bottom not enough to drip or leave a spot) but also has 65-70psi cold startup and 55-60psi warm with 70-75psi at anything 2,000-2,500rpm warm on a STD. volume pump . With that kind of numbers I would hope something had a slight leak from all that pres.
 
N

newmuscle

New Member
Mar 19, 2006
1
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0
Oct 7, 2006
#8
  • Oct 7, 2006
  • #8
Yea had the same looking leak it was coming from those cylinders
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 7, 2006
#9
  • Oct 7, 2006
  • #9
welcome newmuscle :SNSign: what did you do about it?

doesn't it look like it was coming out of the spark plug hole ... ?

would that indicate a blown/broken ring?

I'm pulling the heads next ...
 

SWYZ721

Member
Aug 24, 2004
208
0
16
Ann Arbor, MI
Oct 7, 2006
#10
  • Oct 7, 2006
  • #10
Our rear mains always seem to ooze at least a little bit.
 
8

8950HO

New Member
Mar 31, 2005
658
2
0
Oct 7, 2006
#11
  • Oct 7, 2006
  • #11
Check your PCV system,especially the metal screen under the PCV valve rubber grommet.

If it`s plugged up and restricted,crankcase pressure builds up forcing oil past seals.
 
T

tjh566

New Member
May 22, 2004
608
0
0
Northern Va
Oct 7, 2006
#12
  • Oct 7, 2006
  • #12
yeah, the rear-mains leak alot on our cars, mines leaking a little, its comes with the miles and the years, its minimal so I'm leaving it alone until I can afford a new motor
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 7, 2006
#13
  • Oct 7, 2006
  • #13
here is the head ... #8 looks bad





 

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BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 7, 2006
#14
  • Oct 7, 2006
  • #14
so ...

- the compression test said 165 for #8, the others were around 150

- there is evidence of oil leaking from the #8 spark plug hole

- the #8 compression chamber looks like it looks.

What does it mean? i'm thinking rings (again)



 

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I

iwashmycar

20+ Year Stangneter
Apr 7, 2004
1,236
1
39
Columbus, Ohio
Oct 8, 2006
#15
  • Oct 8, 2006
  • #15
looks that way.... thats a bummer tho

mines been leakin some also, but still runnin like 48-54 on the oil press gauge
 

diablostang

New Member
Sep 21, 2004
425
0
0
Raleigh, NC
Oct 9, 2006
#16
  • Oct 9, 2006
  • #16
To me, it says screw it, and get a 418 stroker
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 9, 2006
#17
  • Oct 9, 2006
  • #17
heh ... don't give me any ideas. i might be refinancing my mortgage anyway and getting like $150,000 cash out ...
 

S/CBlack95GT

New Member
Apr 6, 2003
2,018
0
0
Tampa Palms, FL
Oct 9, 2006
#18
  • Oct 9, 2006
  • #18
My rear main leaks a bit, but it never drips so I dont worry about it. You could take the engine apart and replace all the seals/gaskets if you are bored. If it doesn't drip I wouldn't be concerned though.
 

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
Oct 10, 2006
#19
  • Oct 10, 2006
  • #19
well let me put it this way, i lose a quart every tank, about 200 miles. it's going somewhere
 

blkcobra50

New Member
Jul 24, 2006
209
0
0
Oct 10, 2006
#20
  • Oct 10, 2006
  • #20
The oil in #8 could also be from the valve seals letting oil get into the combustion chamber. Looks a little excessive with oil chasing spark plug threads. The higher compression makes me lean more in the way of valve seals because if the oil was getting past the rings i would think the compression would be a bit lower.

Also looks like a combo of rear main and oil pan gasket leaks. my rear main leak was not as bad as yours looks but that is what pushed me to build motor!!
 
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