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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Let's Play a Game: Oil Pan or Rear Main Seal?

  • Thread starter Thread starter gp001
  • Start date Start date Nov 27, 2004
G

gp001

Founding Member
Jun 30, 2001
4,401
0
66
So. Cal.
Nov 27, 2004
#1
  • Nov 27, 2004
  • #1
I have been driving my car for the past week and finally took it to my new place yesterday. Each time I drove the car this week I noticed a leak after I shut it off. Nothing leaks when running (even idled for 30 min with occasional revs to 5k+ thrown in). The first few times I thought it might be the dreaded rear main seal leak since the oil seemed to run down the outside of the blockplate. But I noticed no oil on the front face of the flywheel. Then I began noticing the oil would leak down the slope of the pan toward the sump and drip off about half way on it's journey. Since I replaced the rear main seal as well as the oil pan and oil pan gasket I am hoping it is the pan/pan gasket.
So, here is my thinking: Since it doesn't leak when running, there is no change in oil pressure, there is no oil on the front face of the flywheel, there is no slipping/chattering/vibration of the clutch, and the oil is dripping from the slope of the pan and not the block plate/scattershield I am leaning toward oil pan gasket.

What do you guys think?

Also, block is 5.0 with 1 piece rear main seal
 

reenmachine

20+ Year Stangneter
Jun 27, 2004
1,258
2
38
Montrose, CA
Nov 27, 2004
#2
  • Nov 27, 2004
  • #2
gp001 said:
So, here is my thinking: Since it doesn't leak when running, there is no change in oil pressure, there is no oil on the front face of the flywheel, there is no slipping/chattering/vibration of the clutch, and the oil is dripping from the slope of the pan and not the block plate/scattershield I am leaning toward oil pan gasket.
Click to expand...
So what do you need us for??? Sounds like you've reasoned it out well. I might say that only when you turn the engine off and all of the oil drains into the pan is the oil level high enough in the pan to leak out the rear oil pan gasket, supporting your theory.
 
G

gp001

Founding Member
Jun 30, 2001
4,401
0
66
So. Cal.
Nov 27, 2004
#3
  • Nov 27, 2004
  • #3
Well, that's kind of what I'm looking for. I want people to either support my reasoning or tell me if I've missed something. I've never had a leaking rear main seal or rear pan leak, so I am just theorizing in the dark. I would hope that others who have more experience than I would support or refute my logic based on their experiences, therefore helping me to narrow down my repair approach.
 

68_stanger

New Member
Nov 21, 2003
131
0
0
Petoskey, MI
Nov 27, 2004
#4
  • Nov 27, 2004
  • #4
I had the exact same problem. My car leaked oil after it was shut off. Mine was the oil pan gasket. Since I was doing it I also replaced the stock oil pan with something a lil bit better. It solved my problem
 

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
0
0
Go ahead, call me cheaky
Nov 27, 2004
#5
  • Nov 27, 2004
  • #5
When my dads 79 300 i6 rear main seal leaked it played havick with the clutch.. but you allready took this into consideration...


I know my buddy replaced the pan gasket on his 77 t-bird 400m and it took him 2 tries.....

lets hope its the pan thats easier to fix :canflag:
-gbm-
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Nov 27, 2004
#6
  • Nov 27, 2004
  • #6
Try doing a recheck of the tork,
the corners were the gasket and end seal meet could be seeping on standing after run.

PB
 
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