01 Overheat/losing coolant

[Drpeckr]

My 01 w/ bolt ons had an issue the other day. Drove in town enough to warm the car up completely. Rolled through several parking lots very slowly, parked, no issue at this point (that I was aware of). After about 5 minutes parked I went to startup the car. Car hesitated and then started (not normal). At start i noticed a puff of steam come from the center/front of my hood area. Noticed that temp gauge was at ~2/3. Not too far from home, started driving slowly home watching temp gauge. Turned on heater full blast. After ~2 minutes of driving the temp dropped back down to normal range where it stayed the rest of the way home ~5 miles.

Last night I checked the car, found no leaks underneath. Checked coolant res. and found it was essentially empty. Filled it up with coolant. Started car, drove around block several times. Found that the car was NOT heating up as quickly as it normally does. Could barely get temp gauge above the low line. Kept driving, car eventually got to normal operating temp on temp gauge. Parked car idling and checked under the front. Found that there was coolant dripping, probably 2-4 tablespoons under the car after idling for 30 seconds. Even after car was at operating temp, I could hold my hand on the radiator, it felt cold to the touch.

I can't see where the coolant is coming from.

Any recommendation on where to start?

 

[3B99SVT]

I'm not sure where your leak is, but it sounds like you have air in the system now and don't recommend driving it far until you fix the leak and properly burp the system. Don't just add coolant to the degas bottle -- you need to top the system off via the coolant crossover. A quick search should give details. When I replaced my water pump, I put my front end up on ramps and put a funnel in the coolant crossover. Then brought it up to temp to let the thermostat open while always keeping a small amount of coolant in the funnel.

Where were the drips coming from: bottom of radiator, front of oil pan, driver's side, other location? Quick checks: Check the weep hole on your water pump for signs of coolant. Check your oil cooler to block seal.

 

[Drpeckr]

Thanks for the reply. After thinking about it overnight I felt like my post was sorta stupid as I didn't really include enough information.

So.. last night I poked around in the engine compartment looking for signs of coolant leaking.. I'm going to do a poor job of explaining this as I didn't take any pics..

The lower radiator hose connects to a metal "elbow" that has multiple hoses connecting to it. One of the smaller diameter hoses appears to have slipped up partially off of the "nipple" it connects to. Tonight I'm going to try to reseat that hose and then do the burp procedure. Hope thats all it was. IF that *IS* what it was, then I'm going to be concerned as to how/why the hose was able to move that far..

Edit: After looking at some pics online, the "elbow" I'm referring to appears to be the thermostat housing.

 

[Drpeckr]

Update: Ordered a Reische 170 thermostat, should be here next week. Until then the snake's just sittin pretty in my garage. Figured no reason to doodle around sticking everything back together and then waste a bunch of coolant testing if I'm gonna have to do it again when the new thermy shows up.

(wild guess as to how this happened involves my existing thermostat getting stuck shut (will test once it's out of the car) which overpressurized the system causing the hose to pop itself loose)

 

[baller1svtcobra]

Can u take pics? I wanna upgrade my thermostat as well but I need help cuz I'm nowhere close to a mechanic jaja

 

[MT0911]

Cool - just make sure you properly burp the system and then check for any leaks after you secure that hose. Good luck man.

 

[Black*Death]

I bet the thermostat is sticking? Wouldn't explain the leak? MAke sure you aren't losing any fluid by the water pump..aka the water pump is failing

 

[RX1Cobra]

If a thermostat fails its usually in the open position and if it got stuck closed you'd know it. The car would overheat and wouldn't have cooled back down after driving. I'd replace the clamp that the hose worked lose on. Maybe it's lost its spring tension over the years. However, I'd say it overheated because that hose allowed air into the system and had nothing to do with the thermostat.

 

[Drpeckr]

After getting under the car and checking everything, I was incorrect about the loose hose, there was NO loose hose. It was the smaller hose running down from the expansion chamber and on the thermostat housing the "nipple" has a lower bump that looks like it keeps the hose from sliding down any further. I went ahead and drained all the coolant (didn't flush, would have liked to but didn't have time and was sick of driving my 4cyl accord coupe/1988 Caddy deville) replaced thermostat with the Reische, refilled coolant reservoir with straight antifreeze (took ~3/4 of a jug), capped the reservoir and started filling the crossover with straight distilled water.
After I couldn't get any more water to go in, followed the burping instructions on Reische's site.
I only went through the burping process 1 time, will probably burp again once or twice this weekend to be sure.
I checked the coolant this morning (car has been driven ~40 miles since the change), found that it was a little lower in the reservoir, guessing because the heater core may have allowed the system to suck some more fluid down or just as part of the cooling of the fluid I put in already.
I added more coolant to the reservoir, will check it again tonight after driving home from work.

So far no leaks that I've seen, crossing fingers.

Honestly, I've owned many Mustang's over the years, mostly Foxes, but a couple SN-95's including a V6 vert and a 94 Cobra (with cloth interior, cali special I heard) and I've always trusted them mechanically. Not sure if its because I've read too much on these forums about all the ills of the 4v 4.6 but I can't seem to trust this damned car.. I trust it even less than one of my Foxes that had 160k+ on the original motor/tranny combo, and my 01 only has ~88k on it..

 

[RX1Cobra]

These motors are tough and will last along time. Just make sure you check your oil and keep it full. They burn some oil through the PCV system.

 

[Black*Death]

After getting under the car and checking everything, I was incorrect about the loose hose, there was NO loose hose. It was the smaller hose running down from the expansion chamber and on the thermostat housing the "nipple" has a lower bump that looks like it keeps the hose from sliding down any further. I went ahead and drained all the coolant (didn't flush, would have liked to but didn't have time and was sick of driving my 4cyl accord coupe/1988 Caddy deville) replaced thermostat with the Reische, refilled coolant reservoir with straight antifreeze (took ~3/4 of a jug), capped the reservoir and started filling the crossover with straight distilled water.
After I couldn't get any more water to go in, followed the burping instructions on Reische's site.
I only went through the burping process 1 time, will probably burp again once or twice this weekend to be sure.
I checked the coolant this morning (car has been driven ~40 miles since the change), found that it was a little lower in the reservoir, guessing because the heater core may have allowed the system to suck some more fluid down or just as part of the cooling of the fluid I put in already.
I added more coolant to the reservoir, will check it again tonight after driving home from work.

So far no leaks that I've seen, crossing fingers.

Honestly, I've owned many Mustang's over the years, mostly Foxes, but a couple SN-95's including a V6 vert and a 94 Cobra (with cloth interior, cali special I heard) and I've always trusted them mechanically. Not sure if its because I've read too much on these forums about all the ills of the 4v 4.6 but I can't seem to trust this damned car.. I trust it even less than one of my Foxes that had 160k+ on the original motor/tranny combo, and my 01 only has ~88k on it..

I think it was your thermostat...I have heard of Thermostats not opening closing completely..aka "sticking".

Not to be condescending, but tires, batteries, plugs, water-pumps, and thermostats are wearable parts IMHO.

Others may disagree but I wouldn't be scared about the reliability...

Hope that was the problem and car runs great

 

[IUP99snake]

He's right about thermostats being wearable parts. Get one of those thermostats that if it sticks, it sticks in the "open" position" instead of the closed position.

Also, check to see if your heater is blowing hot air. If it's blowing cold air when the engine is warm, you most definitely have an air pocket in the engine somewhere and it needs to be burped.

Air pockets can form if the engine overheats and the coolant boils, or if you open the radiator cap when it's hot (and all the sudden the loss of pressure in the system causes it to boil).

As far as losing coolant, you've got me stumped. The only reason I can think it's losing coolant if it's not actually dripping onto the ground is that it has a blown head gasket.

There are a few ways to test for a blown head gasket. There may be testers that check the chemical quality of the coolant. The way I found out about a blown head gasket was to run the car before it warms up and open the radiator cap (degas bottle). Have a buddy rev the engine and see if you get air bubbles coming up out of the degas bottle.

You can also check the oil. You'll notice a milky ring surrounding the oil cap.

And most importantly, check the plugs. Usually, the plugs will be white or a light tan color. On the cylinder (or cylinders if the blown gasket is between cylinders), you might notice a greenish tint on the plugs, or they may be completely fouled. Either way, they'll look different than any of the normal plugs.

Hopefully it's the thermostat. That's cheap and easy to fix.

If it is the thermostat, don't get tempted to get a colder thermostat. The engine is designed to run at a specific temperature. If it runs 10 or 20 degrees colder than that, it will confuse the hell out of the computer and it'll get crappy gas mileage among other things.