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oil pressure

  • Thread starter Thread starter Gandalf79
  • Start date Start date Feb 5, 2024
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Gandalf79

Member
Jun 14, 2023
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Feb 5, 2024
#1
  • Feb 5, 2024
  • #1
Hey I just checked my oil pressure on my 79 fox and when it started cold it was hovering around 46 to 48 and at warm idle, it was at a consistent 22-24. Now I had to test this using an external oil pressure test kit that seemed to do the job but I don't think I had it fully tightened on the block. Wondering if I had fully fastened the adaptor, if the pressure would go up a bit from that22-24 line. I am reading that 20 psi is the minimum line of normal and I do not want to go below that.
I replaced oil sensor and the gauge didnt work but most of my gauges do not seem to be like the tach and oil gauges.
Just recently changed the oil with 10w-30 but I may change it again to hopefully get rid of any sediment in there.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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polk county florida
Feb 5, 2024
#2
  • Feb 5, 2024
  • #2
Are you lost? The fox forums are down the hall on the left, here let me help you move this ........
 

JD1964

there is enough sticking out to grab on to
15 Year Member
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Feb 5, 2024
#3
  • Feb 5, 2024
  • #3
22-24 at hot idle is fine. When you rev the engine a bit the pressure should go up. Does it? How high does it go?
 
G

Gandalf79

Member
Jun 14, 2023
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Feb 6, 2024
#4
  • Feb 6, 2024
  • #4
JD1964 said:
22-24 at hot idle is fine. When you rev the engine a bit the pressure should go up. Does it? How high does it go?
Click to expand...
Yes the gauge reads a higher pressure. I am unsure of the RPMs I was at when I revved the engine but I believe it went back up into the low 40s.
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
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Claremore, OK
Feb 6, 2024
#5
  • Feb 6, 2024
  • #5
Reinstall the mechanical oil pressure gauge with enough plastic line to get the gauge where you can see it. Run the motor and report back.
 
Reactions: General karthief
G

Gandalf79

Member
Jun 14, 2023
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Feb 6, 2024
#6
  • Feb 6, 2024
  • #6
AeroCoupe said:
Reinstall the mechanical oil pressure gauge with enough plastic line to get the gauge where you can see it. Run the motor and report back.
Click to expand...
Okay I will do that this weekend. I am going to get it tightened on nicely to the block and fire it up again. and get back to you. Thank you.
Hoping I don't need to dive deeper into the issue aside from figuring out why the gauge isn't reading. Maybe need a new harness from the sensor to the cluster? Where is the tach reading from? Forgive my ignorance, I am learning as I go on this car. I am also looking for a diagram of the vacuum line for this car.
 

85GTStangGuy

5 Year Member
May 19, 2021
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Jax, Florida
Feb 6, 2024
#7
  • Feb 6, 2024
  • #7
Gandalf79 said:
I am also looking for a diagram of the vacuum line for this car.
Click to expand...
You might find this manual to be helpful...

Digital copy

1979 Mustang Electrical & Vacuum Trouble-Shooting Manual (EVTM) (USB) | eBay

Find many great new & used options and get the best deals for 1979 Mustang Electrical & Vacuum Trouble-Shooting Manual (EVTM) (USB) at the best online prices at eBay! Free shipping for many products!
www.ebay.com

Hard copy

1979 Ford Mustang & Mercury Capri Factory Wiring Diagrams (EVTM) - 0339503 | eBay

1979 Ford Mustang. Wiring Harness Overview. Vehicle Repair Location Charts. Component Location Charts. Component Location Views. Connector Views. Component Testing. Audio System.
www.ebay.com
 
Reactions: General karthief, limp and AeroCoupe
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Gandalf79

Member
Jun 14, 2023
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Feb 10, 2024
#8
  • Feb 10, 2024
  • #8
Gandalf79 said:
Okay I will do that this weekend. I am going to get it tightened on nicely to the block and fire it up again. and get back to you. Thank you.
Hoping I don't need to dive deeper into the issue aside from figuring out why the gauge isn't reading. Maybe need a new harness from the sensor to the cluster? Where is the tach reading from? Forgive my ignorance, I am learning as I go on this car. I am also looking for a diagram of the vacuum line for this car.
Click to expand...
Ok I’m so I was able to get the oil pressure test gauge tight and fired the car up and I started around 48 psi at cold start and it was there for awhile then as it got to hot idle it didn’t go below 20 psi
See videos
Had a question on a hose line that seems to be coming off a port right next to the pcv valve but it’s not connected to anything at the other end
Included a photo as best as I could get it
 

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G

Gandalf79

Member
Jun 14, 2023
61
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Feb 11, 2024
#9
  • Feb 11, 2024
  • #9
Last one was a video but it wouldn’t let me attach the file so I took a screenshot right after starting the car
 

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limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
Feb 12, 2024
#10
  • Feb 12, 2024
  • #10
Gandalf79 said:
Last one was a video but it wouldn’t let me attach the file so I took a screenshot right after starting the car
Click to expand...
That'll work.....
 
G

Gandalf79

Member
Jun 14, 2023
61
13
18
Feb 12, 2024
#11
  • Feb 12, 2024
  • #11
limp said:
That'll work.....
Click to expand...
I think I am satisfied with the oil pressure and that it could be my gauge just not working. My tach is not working either so I have to figure that out. All the other gauges seem to work though.
On to the next thing!
 
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