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

My car is doing it again!

  • Thread starter Thread starter 68stang351
  • Start date Start date Jan 27, 2004

68stang351

Founding Member
May 16, 2002
850
9
39
Savoy TX
Jan 27, 2004
#1
  • Jan 27, 2004
  • #1
Well, it happened again. This is only the second time, and it only seems to do it when its cold outside overnight. Like under 30 degrees.
Here's my first post. http://forums.stangnet.com/showthread.php?t=411576

From where it is at on the ground, it looks like its the back freeze plug on the side of the block on the drivers side. It leaked out roughly a half a gallon this time. It won't do it when it's warmed up and running, or when it's nice outside.

????????????

I'm stumped.
 
S

slapper

Founding Member
Mar 6, 2002
447
0
0
Jan 27, 2004
#2
  • Jan 27, 2004
  • #2
You could try and pressurize the cooling system with a radiator pump when the thermostat is opened(wait for the car to cool for a bit after normal opertaing temp), and get under the freeze plug, and CLOSELY examine the area for leaks. Use a paper towel, as they are HIGHLY absorbant and will pick up the slightest moisture.
What with the rate of thermal expansion of copper vs steel, I suppose it could be static leaking at cold temps??

Or,....if you suspect the freeze plug, just replace it, and be done with it.
 

68stang351

Founding Member
May 16, 2002
850
9
39
Savoy TX
Jan 27, 2004
#3
  • Jan 27, 2004
  • #3
slapper said:
You could try and pressurize the cooling system with a radiator pump when the thermostat is opened(wait for the car to cool for a bit after normal opertaing temp), and get under the freeze plug, and CLOSELY examine the area for leaks. Use a paper towel, as they are HIGHLY absorbant and will pick up the slightest moisture.
What with the rate of thermal expansion of copper vs steel, I suppose it could be static leaking at cold temps??

Or,....if you suspect the freeze plug, just replace it, and be done with it.
Click to expand...

I would think that surely it's not the freeze plug seeing as how the motor is only about 15 months old and has only had a 50/50 mix of antifreeze and distilled water, so it's not rusted. Besides, I can't even SEE that freeze plug, and I really don't want to attempt to replace it.

You expansion theory is interesting though. Maybe that's what it is.
 
S

slapper

Founding Member
Mar 6, 2002
447
0
0
Jan 27, 2004
#4
  • Jan 27, 2004
  • #4
There's also a 3/8" pipe plug on the driver's side of the block fwd of the aft freeze plug by about 2". It may be leaking???
I wouldn't put too much stock into the age of the overhaul vs potential freeze plug leakage. They can leak regardless of mileage.
Were the plugs installed with sealant?
That aft plug is not that hard to R&R. The middle one is the fun one with the engine installed.
 
You must log in or register to reply here.

Similar threads

E
2007 GT Stalls when lights or a/c turned on
  • ejscarfo
  • Jun 22, 2026
  • 2005 - 2009 Specific Tech
Replies
2
Views
182
2005 - 2009 Specific Tech Jun 29, 2026
ejscarfo
E
Distributor installed wrong
  • djj62478
  • Jun 14, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
4
Views
227
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 21, 2026
CAMTWO1070
M
Help! 2003 GT misfire when hot
  • Modular03
  • Feb 10, 2026
  • SN95 4.6L Mustang Tech
Replies
4
Views
455
SN95 4.6L Mustang Tech Feb 13, 2026
Mustang5L5
Considering widening my rear wheels, would like to verify my thoughts on fitment
  • 2000xp8
  • Jul 9, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
25
Views
593
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 6, 2026
85GT4V
B
Electrical Why does my fox body keep frying eecs
  • brandyn200
  • Jun 20, 2026
  • Fox 5.0 Mustang Tech
Replies
8
Views
313
Fox 5.0 Mustang Tech Jun 25, 2026
AeroCoupe
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?