Car overheated on the way home tonight...

[MatthewDavid]

I was just cruisin along and the car overheated... went all the way to the red... it was all of a sudden but it was fast enough that I barely found a good spot to park... the low engine coolant error has been goin off... I've tried getting the air out twice and still don't think i got it all... I got a new thermostat put in about 2 months ago... anyone have any ideas?... it took us about 2 hours to get home and we where only like 10 miles away!!

 

[unity]

Only three things should really cause it to over heat. Air in the system, bad pump or bad t-stat. If the car complains coolant is low and you have filled it, that could be a sign of a leak. If coolant can get out air can get in.

 

[MatthewDavid]

I had it pressure tested and there wasn't any leaks... yeah I was thinkin it might be the pump now... that sux... how much do those run?... I'll probably have someone put it is for me since my girlfriends little sister is in town and won't have time... always happens at the worst times!!

 

[XLRVIII]

Changing the water pump is stupid easy.
Hardest part of the job is getting all the air back out of the system.

Seriously..
loosen the 4 bolts on the water pump pulley
remove the belt
I took my alternator off {two bolts, and two wires)<-Easy
then pull the bolts holding the pump in.. it's not like most other ford motors where "every accessory is hung off the water pump".

on a 1-10 scale I'd say this is a "2".. just a little harder than changing a tire.
start to finish should only take an hour, if you take your time.

hell.. it'll give you a reason to get away from the G/friends little sister for an hour.

 

[The Rev]

Getting it out on mine was the hard part. The pulley and pump had pretty much been rusted together. Its honestly not hard though, I used a baseball bat to loosen it up, then pried it off against the crossover pipe. Getting the air out was my problem.

 

[MatthewDavid]

So I took it to a shop to get it diagnosed... what they said was they let it idle for 45 minutes... it didn't overheat... they took it for a test drive and it hit the red right away... they said it might be the pump just wearing out... but could it be the head gasket?... that would really suck... but what would the symptoms be if it was?

 

[unity]

I am betting air in the system. When the pump starts turning coolant hard it can "foam" it up and make it hard for it to flow right.

I would check for air in the cross-over first.

 

[The Rev]

Does your exhaust smell sweet? You can check that easily enough. Also, I've heard that you can lose coolant through the exhaust (if you cant find a leak). Look at the oil, it could be milky, people say that coolant gets burned off and leaves a milky residue on the underside of the oil filler cap as well.

When I had my problem I just assumed headgasket because I'm an idiot. My waterpump was spewing coolant everywhere. After replacing it I drove for 2 days and was fine, but then when I got caught in traffic I overheated. My car also could idle and not overheat. When I put it in drive it did overheat. I couldn't get the crossover cap off to get the air off properly. Burping these beasts is tricky, have the car on a slight incline when you start. Do a search on it, poniesviii had an easy to understand description.

 

[MatthewDavid]

I told them that's what I was thinking... but I figured should get things checked first... if it was the head gasket there would be coolant in the oil right?... well I did the pepsi challenge and tasted it and it tasted like oil... nice and greasy no bit of sweetness... so I'm kinda crossin my fingers and ruling it out... and I know I've been having a lot of problems getting the air out... what you're sayin makes sense... since the coolant says it's low and it's about full... could just be a lot of foam in there... could the radiator have anything to do with this stuff?...

 

[Aquabrit]

if it was the head gasket there would be coolant in the oil right?

Sometimes, not always. As others have said, likely air in system. Never heard of head gaskets blowing on this engine unless over heated. Not a common problem.

Bleed and fill a few more times before coming to any conclusions.

 

[98CobraStarLSC]

check your cap!!! on the coolant resevoir! had mine go bad and it was the last thing i checked but it was definately bad. put a new one on and no more problems...

 

[MatthewDavid]

Hmmm never thought of that... how would I know if it's bad?... maybe the whole tank is?... I was looking at it and there's a crack in it... but it's not leaking so I don't think there's any air gettin in... figured if fluid is stayin in then air shouldn't be able to... but you guys have been a great help... I had a guy burp and refill it and it's stayin normal at the moment... gonna take it for a short drive tonight to see if it changes... I might just order a new tank just incase that's what it is... it's just a PITA... who designed this awesome cooling system... the government?... hehehee... I'm sure it's good... just man talk about troubles!!

 

[Abbens]

maybe the gasket on the cap and if you do replace it please replace it with the same pound cap

 

[Demoman]

LOL the pepsi challenege!

 

[thaywood]

I have had the same problem for a couple of years on my '96 Mark. It would not "overheat", but it would get to the top of the Normal section, just under the "N". I flushed and burped the system several times to no avail. Even had a shop install a new thermostat because I didn't want to mess with it. Didn't help. The cooling fan was working fine and there was no air in the system that I could see. Recently, it had begun to get worse and I started getting a "low coolant" warning, even though the reservoir was completely full. The low coolant turned out to be too much water and not enough anitfreeze. It turns out that the little float in the reservoir is apparently designed to float only when there is enough anitfreeze in the system. When there is too much water, it will sink. Neato huh? Anyway, I found a Stant 160 degree thermostat for a Mustang Cobra on Ebay and installed it. Since installing the new T-stat, the thing has run great and the guage barely gets to the bottom of the "M" on 90 degree days with the AC at full blast. Increrdible. I have always thought that a 195 degree factory thermostat is waaaay too hot for an aluminum block engine. Anyway, this may not work for everyone, but it sure worked for me. Hope this helps. And remember, when you replace the t-stat, you will get antifreeze all over you and everything around you. And you will have to refill the system and burp it again.

 

[unity]

I did not know the water/coolant mix thing. Really? Kinda cool.

 

[thaywood]

I did not know the water/coolant mix thing. Really? Kinda cool.

I know. I didn't realize it until I looked at the coolant in my reservoir and it was a little too clear. It was full and I could see the float at the bottom of the tank. I syphoned out the water and added antifreeze and the float came up as I filled it. I don't know if purposfully designed that way, but that's what it looks like to me.

 

[unity]

Well if so that may explain the "problem" some have with the sensors, the sensor may in fact be fine.

 

[MatthewDavid]

Maybe that was it... cause I took it to a shop and they finally got it to work... they went through and pressure tested everything and no leaks... they checked the headgasket nothing... the flushed the radiator and there was a little debris in it but nothing major... but I do know the tech that filled it before filled it with half and half coolant... well this time the guy put almost only antifreeze in it... with just a little water... like 25/75 mix... they wanted to make sure it would stay cooler they said but it works fine now... the error doesn't come up anymore and it runs really nice... seams like I even got more MPG too... but that's just me hopin probably ... but that's nutty a little thing like that could be the cause