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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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When engine runs for 20-30 mins oil pressure drops

  • Thread starter Thread starter StangBangRicers
  • Start date Start date Jan 20, 2004
S

StangBangRicers

New Member
Dec 9, 2002
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Jan 20, 2004
#1
  • Jan 20, 2004
  • #1
Is this normal? Should I be concerned?


Usually my oil pressure stays at about 2 lines before the 100 limit. However it drops to the line above the (oil can with drip) symbol when it is running hot. Even when I bring it up to normal running temp it is fine. Just after 20 mins or so of running it drops.

It's almost like heat soak is having some affect on oil pressure.
 
R

redterror302

Founding Member
Jun 29, 2002
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Mertztown, PA or State College, PA
Jan 20, 2004
#2
  • Jan 20, 2004
  • #2
That happens to me too, I think it is normal though. It would make sense because when it is cold, the oil is thicker and creates more pressure, but when it is warm, the oil is more viscous and reduces in pressure. It only happens to me when idling though. Once I start going again and bring the rpms up a bit, it goes back. I don't know what yours is like though.

Not sure if I helped, but thats the way mine is.

Chris
 

bgjohnson

Founding Member
Sep 1, 2002
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johnston,iowa
Jan 20, 2004
#3
  • Jan 20, 2004
  • #3
I think that means your stock oil pump is a little worn.
 
J

jerry beach

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May 20, 2002
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Ocala,FL
Jan 20, 2004
#4
  • Jan 20, 2004
  • #4
It takes much more time for oil to heat up than the coolant. As the oil gets hotter press. will drop. That is normal. It takes about 30 min of driving for the oil to get all the way up to operating temp. Get a real guage and look for at least 10psi for every 1000rpm. Thats what you should be looking for.
 
S

StangBangRicers

New Member
Dec 9, 2002
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Jan 20, 2004
#5
  • Jan 20, 2004
  • #5
It only happens to me when idling though. Once I start going again and bring the rpms up a bit, it goes back.
Click to expand...


Exactly...
 
S

StangBangRicers

New Member
Dec 9, 2002
58
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0
Jan 20, 2004
#6
  • Jan 20, 2004
  • #6
jerry beach said:
It takes much more time for oil to heat up than the coolant.
Click to expand...

That explains it...


Thnx!
 

mike keirstead

New Member
Aug 6, 2003
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ROLLING A JOINT
Jan 20, 2004
#7
  • Jan 20, 2004
  • #7
Also the FORD gauges are just dummy lights. Sometimes the sending unit gets a little wore out. They send the voltage to the gauge in the dash. If you want to see you real pressure hool up a MECHANICAL oil pressure gauge and that will tell you.

Most stock 302s don't have alot of oil pressure when they are hot and idleling. But the gauge will show you true reading.

I was getting 50-60 psi cold and 15-25 hot on the stock gauge and I hooker up my autometer and I was getting 55-60 cold and 30 or so hot.
 
1

1BAD89GT

New Member
Jan 2, 2004
87
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0
Oklahoma
Jan 21, 2004
#8
  • Jan 21, 2004
  • #8
Yeah get a Manual gauge stock electric gauge is not very accurate my pressure drop 5 to 10 psi after driving long period usually 60 to 65 at cold start and idle then it drops to 50 to 55 at idle after driving for a while.
 

Black Sun 5.0

Founding Member
Mar 23, 2002
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36
L.I., N.Y.
Jan 21, 2004
#9
  • Jan 21, 2004
  • #9
I had the same problem, it turned out to be a bad oil pump.
 
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