My car is doing it again!

[68stang351]

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.

 

[slapper]

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]

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.

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.

 

[slapper]

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.