93 Sentra Overheating

Last week I noticed that steam was coming from underneath my hood when I pulled up to a station to refuel. My overflow reservoir is cracked, so it doesn't hold water. When I opened my hood, I saw that the water from the cooling system had flowed back into the cracked tank which is always empty. After the car cooled down, I filled the radiator with water and drove it home without any problem.

After I got home I verified that my cooling fans were running. Since then, it hasn't overheated, although it does run between 1/3 and 1/2 of the temperature gauge. In the mornings, on the way to work, I run the heater since it's cold outside and sometimes it doesn't go up at all. In the evenings, I have to keep an eye on it though, since I'm not always running my heat.

I was told to replace the thermostat but it is not in the position indicated to me. Apparently the top hose running from the radiator is supposed to connect to the thermostat housing? Perhaps my Sentra is different. Is this housing on the front side of the engine? Can someone give me a point of reference? I called a garage and they said it would cost $170 for labor to change it, even though the nearest auto parts store said the part itself costs $8 and requires the removal of three bolts and the purchase of a tube of silicone to complete the repair.

Does it sound as if something is wrong with the thermostat? If so, how can I go about replacing it? I've just relocated and taken a new job and can't afford the repairs, much less to be without a car. Any help or advice is appreciated.

Reply to
Rodney.Wolfenbarger
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How many miles are on the car? Was it HOT that day?

East-

Reply to
eastwardbound2003

It has close to 180k miles on it. And it was about 60 degrees or so outside. Not particularly cold or warm.

Reply to
Rodney.Wolfenbarger

Well it's about about time. At 180,000 miles of service you would think a metalic spring incased inside hot steamy acidic liquid would fail only after so long.

Thermostates were not meant to last forever. Replace it. And if you have more problems keep in mind that the water pump might be going bad and isn't pumping as much as it normaly should. FIX your fluid reservoir ASAP. Do you think the brightest minds working in the automotive industry would have saved the extra billion to leave those reservores out of the design if they were entirely unecessary? Unless you love getting strated out of the middle of nowhere. Just fix the damn thing. What's $10 for a fluid reservor vs. $1,000 for towing, storage, hotel, repair and taxi fees.

Logic and Physics helps out in the handy mechanic gig. Especially if you wanted the correct diagnosis and not some wield guess.

East-

Reply to
eastwardbound2003

It's possible the only current problem is the broken overflow tank.

Every time the car gets to normal operating temp, some coolant goes into the overflow tank. When the engine cools down, it draws the fluid back into the radiator/cooling system (that's why there's a hot/cold level on it). with the tank broken, it can't draw the coolant back, so it gradually looses coolant (possibly to the point of overheating.) I'm guessing you have a 1.6 liter motor. I had a 2 liter, which has a air bleeder screw to get the air bubbles out of the motor/block. If 1.6 has that, you may need to bleed it also...

Gary K

Reply to
gary

Gary,

Thanks for the explanation. I ordered a reservoir tank and will see if that takes care of the problem. It is a 1.6, but is it necessary to bleed the block? Usually, I have my dad or brothers take a look at it every time I travel home. As you can tell, I'm not very informed about mechanics myself. If this is necessary, I'll have someone else take a look at it before I try to drive it a few hours home over Thanksgiving.

Thanks, Rodney

gary wrote:

Reply to
Rodney.Wolfenbarger

If your heater has gotten spastic then, yes, you need to bleed the block.

Reply to
E Meyer

While this method is not perfect, it'll help to bleed the system. do this on a COLD car(and, of course after you have replaced the broken reservoir tank):

Take the radiator cap off.

Make sure the coolant is filled up to the top, or at least covering the metal you see as you look inside the radiator.

Start the car and let it idle.

Because the car is cold the thermostat will stay closed and you will not see any flow inside tyhe radiator.

As the car warms up you should start to see the coolant start to flow.

You may want to push the accdelerator cable a little to force the water pump to push harder to get the water flowing, and hence the air out, and to get the car to warm up faster so the thermostat opens fully.

When the car gets warm coolant should be steadily flowing and any air trapped in the system will simply escape out of the open radiator cap.

Now, the car will get warm to the point that the coolant will come all the way up and spill over. It will not go into the resevervoir because the cap is off.

Once you've reached that point, turn off the car and put the radiator cap back on. When putting the cap back on sure there the coolant is overflowing, in other words putting on the cap make coolant spill out. That's a good thing.

You should be good after that.

CD

Reply to
Codifus

Codifus, good post.

I would only add that it helps if you have the hearter to the max (stop-c*ck valve open) and if the radiator is highest (as having the car parked on an incline going up).

That was the > snipped-for-privacy@gmail.com wrote:

Reply to
AS

What a damned good idea. I have to do my mother in law's 99 Quest at some point, that's a very tricky car to do a coolant change on, and I'll do it in the driveway pointing uphill.

Thanks!

CD

Reply to
Codifus

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