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Common 5.0 oil leaks?!?

  • Thread starter Thread starter Slo5Oh89
  • Start date Start date Jan 30, 2011

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Jan 30, 2011
#1
  • Jan 30, 2011
  • #1
I have a '89 convert with 71K. I am starting to find oil spots. I have replaced the valve cover gaskets over a year ago. Really seemed to slove the problem. I have seen where its been leaking oil under the car like maybe the rear main seal? But the mechanic who changed my clutch said the Rear Main Seal was fine. Any ideas or more info you need. I have to add a quart around time for each oil change. I use 10W-30 full synthetic.
 

wythors

Get off my lawn!!!
Founding Member
May 17, 2000
2,277
35
69
C Addle
Jan 30, 2011
#2
  • Jan 30, 2011
  • #2
Oil pan is very common.
 
8

87AODGT

Founding Member
Jan 6, 2001
373
1
19
Toms River, NJ
Jan 30, 2011
#3
  • Jan 30, 2011
  • #3
where the intake manifold meets the block in the rear of the engine, the cork gasket there is known to be a leaker. I used black RTV there every time I ever took a manifold off and never had a problem like the cork gasket gives ya
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
Jan 30, 2011
#4
  • Jan 30, 2011
  • #4
Rear main is the only problem I always have with oil leaks. Also my valve covers are leakin but I have cheapo valve covers that I need to swap out..
 

7upstang91

10 Year Member
May 30, 2008
936
124
74
Florida
Jan 30, 2011
#5
  • Jan 30, 2011
  • #5
All of these are great places to look. ^^^
 

NIKwoaC

中國製造
15 Year Member
Oct 31, 2006
5,525
943
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Chengdu Province
Jan 30, 2011
#6
  • Jan 30, 2011
  • #6
wythors said:
Oil pan is very common.
Click to expand...

Yep. Don't be surprised if you get under there and the bolts are barely finger tight.
 

skunk21

Active Member
May 22, 2007
1,203
3
36
Taxachusetts
Jan 31, 2011
#7
  • Jan 31, 2011
  • #7
everyone hit the good ones but mine pretty much had all these at one time,

Rear of the lower intake

valve covers

oil pan/ low oil level sensor on the side of the pan

rear main
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Feb 1, 2011
#8
  • Feb 1, 2011
  • #8
Ok I think the low oil sensor had oil on it. There a o ring or gasket on that? Also it hard to check torque on oil pan bolts like a lot of them hard to get to?
 

Mikey1968

Member
Nov 1, 2003
232
0
17
Kommiefornia
Feb 8, 2011
#9
  • Feb 8, 2011
  • #9
Don't rule out the valve cover gaskets...I've seen el cheapo corkies go out pretty quick..also, they can relax and need a cinching. Best bet is to use the steel core rubber gaskets....seems to work great!
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
Feb 9, 2011
#10
  • Feb 9, 2011
  • #10
The low oil sending unit has its own gasket. Only like 5 or 6 dollars from Ford. Its like a big rubber washer looking thing. I have one in my garage that I bought but never used it haha.
 

hollywoodstang

Active Member
May 23, 2006
1,095
2
36
Feb 9, 2011
#11
  • Feb 9, 2011
  • #11
front crank seal,
rear main seal,
valve cover gaskets,
intake manifold gaskets,
oil pan gaskets,
oil pressure sensor,
oil level sensor
power steering pump leak
power steering pressure hose
rear tailshaft seal
transmission speedo gear
rear end cover seal/gasket
rear end breather fitting
thermostat housing gasket
timing cover gasket
water pump gasket

These are the leaks that i experienced from my 5.0
 

kowalczyk86

Member
Apr 26, 2010
85
0
7
Feb 9, 2011
#12
  • Feb 9, 2011
  • #12
87AODGT said:
where the intake manifold meets the block in the rear of the engine, the cork gasket there is known to be a leaker. I used black RTV there every time I ever took a manifold off and never had a problem like the cork gasket gives ya
Click to expand...

I think that is the problem that I am having. There are some stains if you look in my upper intake and I wasn't sure what it was.



 

Mikey1968

Member
Nov 1, 2003
232
0
17
Kommiefornia
Feb 10, 2011
#13
  • Feb 10, 2011
  • #13
PCV gasket maybe?
 
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