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Antifreeze Leak

  • Thread starter Thread starter pizon
  • Start date Start date Jun 19, 2009

pizon

New Member
May 6, 2006
14
0
0
Midwest
Jun 19, 2009
#1
  • Jun 19, 2009
  • #1
1997 V6 3.8L manual
I'm leaking antifreeze. The radiator is not leaking and the cap is good. I replaced the thermostat and ring about a month ago. I do not believe it is leaking from the water pump. The lower radiator hose, driver's side, has a drip at the lowest part that appears to be coming from the end that connects to the engine. There is coolant on the area right behind the oil filter, (transmission?) and below that, (camshaft?). The car does not run hot all the time, it's rather sporadic, although it has never reach the red line. My oil is fine, not milky and I do not have any white smoke. Any help would be greatly appreciated.
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jun 20, 2009
#2
  • Jun 20, 2009
  • #2
You sure your water pump isn't leaking? Check where the pump is mounted to the timing chain cover + the small weep hole at the bottom + heater hose connection + where lower radiator hose is clamped on to pump. Hose could have a small pinhole leak right underneath the clamp itaself. Other common leak points to check - cylinder head where it mounts to block and lower intake , thermostat housing area (especially on the lower side) -. The cylinder head + thermostat area is a common place for leaks to occur. Look for small puddles collecting on top of the right side of the water pump. When any of these leaks occur, the runnoff will go all the way down to the lower radiator hose and oil filter depending on how bad the leak is. It wont be the transmission. Only automatics use cooler lines, and those will be transmission fluid.

Best way to find out where the leak is coming from, clean your engine. Hose it off (cover alternator and battery). I would reccomend using Simple Green as it will not corrode or discolol alluminum surfaces.Spray it liberally, then as soon as you'e done spraying, wait about 1 minute then hose it off real good. After your done hosing it off, let it sit for about an hour (so most of the water dries up). Start it after the hour and pinpoint your leak. Oh, don't forget to remove the items covering your alternator and batt.
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jun 20, 2009
#3
  • Jun 20, 2009
  • #3
Dumb phone , Dupe post, see below.
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jun 20, 2009
#4
  • Jun 20, 2009
  • #4
There is one other possible leak source. I didn't think of this at first as it's not real commonplace. Check the freeze plugs on the engine block. These are small (1" - 1 1/2") round metal caps. They are inverted (sunk in) in to multiple spots on the lower side of the block. They plug up coolant passages inside the block. If one of these were to leak, you may see this right where you are noticing it.
 

pizon

New Member
May 6, 2006
14
0
0
Midwest
Jun 21, 2009
#5
  • Jun 21, 2009
  • #5
Thanks for all the input. I'll be trying this today.
 

pizon

New Member
May 6, 2006
14
0
0
Midwest
Jun 21, 2009
#6
  • Jun 21, 2009
  • #6
Okay, I cleaned everything off and it appears the leak is coming from somewhere near the lower hose, but I can't quite see where. The hose is clean near the clamp, but about 2 inches away, on the water pump, it's wet. I can't find the weep hole to save my life!
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jun 21, 2009
#7
  • Jun 21, 2009
  • #7
There should be two weep holes. One on top and another on bottom. Look at the pump pulley,now look immediately behind the pulley on the pump. The weep holes are about an inch from the end of the pump. They are very small (about the diameter of a pencil eraser) . If you can see the one on the top, then follow that same spot to the bottom.
 
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