'99 Escort overheats, heater blows cold air

[RobertJDuncan]

Hi gang,
First post. I just want to verify my suspicions. Two nights ago, my heater started blowing cold air. I turned off the heater, waited a few seconds, and turned it back on. The air was hot for a few seconds, then got cold again.

I checked my coolant levels, and the reservoir was overfilled, but my radiator cap was cold, and when I opened it, the radiator was empty. I figured I had a bad radiator cap, so I replaced that. When I tested the car with the new rad. cap, I let it warm up, then felt the cap. It wasn't hot, but when I opened it slightly, coolant spewed out. I figured that was the problem.

When I drove to work today, it started blowing cold air again, and my temp gauge started creeping up. I kept the heater running, but the temp gauge stayed high (just below the red). At stop lights, and if I dropped the car into neutral to coast down a hill, the temp gauge would drop, but as soon as I started moving again, it would heat up again. Once in a while, it would hit the red line on my gauge, and then my heat would kick in (only when it was in the red).

I'm guessing it's a thermostat, but I want to verify because I can't imagine why it would work intermittently. Like that. My resevoir still has LOTS of coolant in it.


Thanks,

Bob

[Davescort97]

First off, you need to drain and flush the system (including heater core).
Then, replace the thermostat. The symptom of no coolant in the radiator makes me think (I don't very often) the head gasket is gone and pressure is building up in the cooling system. Is there any coolant in the oil? Is there any oil in the coolant? Is the upper radiator hose getting hot after warmup?
If not you probably need a thermostat.

[RobertJDuncan]

The upper radiator hose is getting hot. The coolant is bright green (no brownish muck that I'd expect if there was oil in it). The oil doesn't look like there is coolant in it (doesn't smell like burned coolant either).

Today, like I said, the radiator is full.

Bob

[AzTumbleweed]

Those are symptoms of a blown head gasket. If it were the thermostat then the heater would work. I've been through this a couple times. Sometimes if you take off the radiator cap you can see air bubbles coming up in the coolant.

[RobertJDuncan]

I did see some bubbles in the reservoir...Is it tough to change a head gasket? I'm reasonably mechanically minded...Moreover...I've looked around and see that I can expect to pay more than $1,000 to get it replaced in a shop...with 150,000 miles...is it worth it to replace it?


Bob

[yotermanic]

If you are fairly mechanically inclined, you should be able to do the head gasket. These head gaskets weren't hard to do, but head gaskets are major engine repairs. To check for a head gasket, you could do a compression test, but there's a quick way to check for coolant intrusion. Pull your plugs, are any of them green? Are any of them steam-cleaned? If they are, there's your leak. I think you're going to find a water pump that's leaking, though. Not sure why, but that seems to be more common on those engines than head gaskets.

[yotermanic]

If you are fairly mechanically inclined, you should be able to do the head gasket. These head gaskets weren't hard to do, but head gaskets are major engine repairs. To check for a head gasket, you could do a compression test, but there's a quick way to check for coolant intrusion. Pull your plugs, are any of them green? Are any of them steam-cleaned? If they are, there's your leak. I think you're going to find a water pump that's leaking, though. Not sure why, but that seems to be more common on those engines than head gaskets.

[AzTumbleweed]

When I used to work in a shop we had a test kit that detects exhaust gases in the coolant. Not sure where you get one though.

[smkdamicz]

My escort did that after i replaced the head. I had air caught in the system. Once I got the air out it worked great.

Go ahead replace the head gasket, it's not that hard it's just time consuming. You have to take a lot of the surrounding parts off, i.e intake and exhaust manifolds, timing belt,. Might as well pull the head off and clean the piston heads, but be gentle and don't create scars.

i actually enjoyed doing it and a new head was only like 250 on ebay. With the way the valve seats go, and your right around the time they go 150000, if you have the spare cash and time replace the head....do it

Good luck

Dave

[denisond3]

Another cause of overheating, especially in colder-than-normal winter weather: With insufficient antifreeze in your coolant - the coolant will turn into slush in cold night-time temperatures. Then the slurpy coolant wont move through the heater (or only flow a little), which would explain a lack of heat inside the car. It would also explain a radiator that was cold or seemed 'clogged': Again, lack of flow. And that could make the water temp gauge head for the "hot" side. Admittedly a very low coolant level would have similar symptoms to what you describe.
Before taking the head off, I would try to drive the car some more, to see if it continued to gobble coolant. But if it spews bubbles out the radiator cap when starting the engine from cold - then a head gasket is gone for sure. We had a very slow leak in coolant for a year on our 92 Escort - and my sister-in-law kept driving it daily. Finally the gasket burned through, and she was at the side of the road with steam everywhere. It turned out one of the headbolts had snapped, probably many months earlier. The head got replaced (by me on a weekend) with a rebuilt one. I also did the water pump replacement at the same time, since it was now easy to reach, both radiator hoses new, and of course a new timing belt and idler. That lower radiator hose was hard to get back onto the water pump 'inlet', so Im glad I did that before I reinstalled the exhaust manifold!
I like to work with the car propped up on blocks/wood chunks or jackstands, placed under each side of the body, about where the front door hinge is. Its easier on my elderly back that way, and easier to retrieve the things you drop into the dirt. You will also need a jack holding up a wood block under the engine oil pan, for when you remove the motor mount.

[RobertJDuncan]

Thanks gang,
I replaced the thermostat (figuring that in any case, I need to fix the thing that causes the overheating. Then, with the new thermostat in, I saw the bubbles in my radiator, white smoke coming out my tailpipe, and a rough-running engine. So, instead of fighting with the head gasket in the cold, I flushed the system and put in a bottle of K&W nanotechnology block sealer. I followed the instructions exactly and it's working now with no smoke and no overheating (heater does work) and smooth running engine.

I know people consider those sealers snake oil, but it's working now. I don't use the car for anything but commuting to and from work. If I start to have problems again, I'll replace the head gasket, but until then...

Bob

[denisond3]

Thanks for the feedback, and I hope you will let us know how it goes. It may last weeks and weeks, and we'd be glad to know that. I would bwe surprised if it lasts forever though; thinking of all the engine heads I could have NOT worked on!

[RobertJDuncan]

You were all correct...it didn't last. Yesterday it overheated again, and I could see steam whistling out of the overflow tank. I could also see the metallic flakes from the stop leak substance.

It's at the mechanic's now. He estimated $800-$900 and my wife convinced me to let him change it. She said it's not worth the stress and work for me to do it myself (who am I to argue). So...snake oil it was!

Thanks for all of your help. It was a welcome temporary solution, but in the end, I probably should have just taken it to the mechanic up front.

Bob

[RobertJDuncan]

Another follow up.

The mechanic talked me into replacing the water pump, timing belt, and serpentine belt at the same time (an additions $300) because these are original parts in the car and there will be no additional labor charges....so it's going to cost a little over $1,100, with the head being sent out to the machine shop to be checked and serviced if needed.

Bob

[denisond3]

Your mechanic advised you well; Its the smart thing to do. Now you can forget about the serpentine belt, timing belt, and water pump for the next 100,000 miles. I hope he included replacing the timing belt tensioner pulley, and the lower radiator hose. (The lower radiator hose is a b**** to reach for replacement - unless the front accessory bracket is removed).
I have not had my Escorts long enough to need to replace the serpentine belt again (I rebuilt the engines in both of them & replaced the serpentine belt at that time - Along with replacing the 2 pulleys, for the serpentine belt tensioner and idler). If your mechanic hasnt replaced these its not a big deal to replace them yourself at some point in the future. Its maybe a 30 minute job. Both of these pulleys have relatively small bearings in them - which are not able to be greased.
And thanks for the info on the cost. Since I do all my own work I dont what such jobs cost for labor.