Is This Temperature Safe?

[Retardo]

I recently acquired a '96 Lumina with a blown transmission for $500.. Replaced the transmission and all ourselves. Question is, the temperature guage reads that the engine warms up to about 125-130*F going down the road. With the AC on, the engine will warm to about 140*F. When I come to stop lights, or let it idle for a few minutes, the temperature climbs up to about 200, and the cooling fan turns on a little past the middle of the guage. Is this a safe operating temperature to have the engine operate at 130-140?

At 130-140, there's coolant in the upper radiator hose, but not alot. As the car gets warmer, the hose gets more water in it, and at 200, the hose is slam full of coolant. Does this mean the thermostat is working correctly, and the thermostat is regulating the temperature of the engine correctly? Could it be that the thermostat installed is a "cool running" thermo? I don't know a lot about the cooling systems on cars, and don't know if certain cars run at certain temperatures. Could anybody help me out? This is making me worry a lot since after installing the transmission, the lower instake gasket blew.. I sure don't want that to happen again (blew due to one of the water jackets were stopped up)

[Bruticus]

I also have the same problem with my lumina its a 95 model. Could be that u need to change the thermostat i still havent figured out what the problem is with that yet.

[Retardo]

I drove it on the interstate tonight for 15 miles (total) coming home and the temperature mark never left the 110 mark on the guage.

[Bruticus]

Originally Posted by Retardo

I drove it on the interstate tonight for 15 miles (total) coming home and the temperature mark never left the 110 mark on the guage.

Ya when yur driving on the highway it will never go over 150 but once u sit still for a while it will look like that sucker is gonna hit the red.

[Retardo]

I know that, I'm saying that ANY driving, whether it's city or interstate, the temperature never goes above 130 while drivng. With the AC on, it looks like it's about 140

The 3.1L engines are stock with a 195 degree thermostat, and the fans kick on at 225 degrees.

[Retardo]

Problem: Fixed
Solution: Replaced Thermostat

Apparently, the thermostat that was in the system, was all corroded and shit, which caused it to be stuck open. The thermostat was 195* thermostat, which is stock for the 3100 engines (195* thermostat, 225*F is when fans kick in)

Now I don't have to drive 10 miles for the torque converter to lock in. With it working correctly, the torque converter comes up to temp just like it should, within 2 miles of driving.

[Bruticus]

Originally Posted by Retardo

Problem: Fixed
Solution: Replaced Thermostat

Apparently, the thermostat that was in the system, was all corroded and shit, which caused it to be stuck open. The thermostat was 195* thermostat, which is stock for the 3100 engines (195* thermostat, 225*F is when fans kick in)

Now I don't have to drive 10 miles for the torque converter to lock in. With it working correctly, the torque converter comes up to temp just like it should, within 2 miles of driving.

Did u replace the thermostat by yurself or did u take it to a mechanic because i tried to do it myself and it was a pain. Since the thermostat in yur car was all corroded this might be the same problem with my car.

[Blaze420]

What you need to do is get a better thermostat.

[Retardo]

Yea, I did it by myself. Believe me, it was a PAIN in the ass. What I did was, used a 13mm 1/4" socket with a 6" extension to get to the top bolt of the thermostat. You have to stick the extension between the water pipe and the exhaust, then connect the socket to the extension for it to have clearance to get to the top bolt. The top bolt was pretty easy to get off, so you shouldn't have problems with that.

As for the bottom bolt, you'll need a 13mm wrench, and it should be a 12 point since you can hardly get a bite on it. You'll have to come at it from the rear side of the engine, going to the front. The exhaust pipe, where it begins to wrap behind the engine, if you lay the wrench on the pipe and aim it towards the bottom bolt, you'll be able to loosen it that way. If it's like mine, it's real hard to break it to loosen. Once you do a few of the little bites to loosen it, you should be able to stick your hand under the bolt (lay the back of your hand on the transmission and go between the engine and the exhaust. It should spin pretty easily).

Once you get the bottom bolt loosened and you feel that it's about to fall out, STOP! Tighten it back up enough just so the screw has a bite in the engine. The thermostat is engineered to come out with the bottom screw still in (It's one of those slip-type things where it slips over the screw).

When trying to put the thermostat housing back on, it's best to disconnect the upper radiator hose from it when putting it back on. You'll have to get it on there just right for it to slip over the bottom bolt, and be careful not to move the thermostat too much while trying to put it on, as it will move the gasket on the thermostat and cause a leak.

One thing we did forget to do while filling the coolant back up... Take the screw out of the thermostat housing (bleeder screw) while filling the radiator with water. If not, it will create an air pocket and water won't flow. We started the engine and the temperature went sky high within a matter of seconds.. a quick feel to the upper radiator hose revealed nothing in it. Fill the radiator until water begins to come out of the bleeder screw. Once it's come out, put the bleeder screw back in and the engine has enough coolant in it. Then fill the coolant box to the appropriate level.

One other thing, if the engine is hot when doing this, get a rag and dip it in water. Lay it on the transmission so you won't burn your hand, and if you got an air compressor, you can use it to blow the exhaust pipe to cool it. We got weird ideas.. lol

Sorry to make you look like a dumbass, but I described it the best I could in case there's somebody else out there that might have this problem. Doing it the way I described, it took an hour to remove and install a new thermostat, and of course, the engine was hot when we replaced it.