Overheating Issues! Again!

[DrgnLdyLizHicks]

Here's a stumper for you!

Ok, so to start with, I have a 96 Lumina, 3.1L V6. It overheated, badly, and warped the heads. Got that fixed, and things seemed ok . . . until we tried to drive. We didn't even make it out the garage before it started overheating again. We replaced the water pump, radiator, hoses, temperature sensor, low coolant sensor and thermostat, and things were looking up. Then it did it again. We checked everything, making sure it was connected properly and the everything was running as it should, but we still couldn't drive it. The fans refused to come on, so we wired them to a switch in the dash so we can turn them on manually, and that helped for two days. Then the fan started cutting into the upper radiator hose, so we had to replace it again. On the drive home, the lower radiator hose came off at the radiator.

We've tried everything we could think of, but we're still unable to fix the issue. Any and all help would be greatly appreciated. Thanks in advance. I'm about ready to give up on it.

[Schurkey]

Is it actually overheating, or are you blowing compression pressure into the cooling system through a non-sealing head gasket or a cracked casting?

What temperature is the coolant; and how are you measuring that temperature?

[jeffcoslacker]

If the cooling system was not bled correctly, the fan temp sensor and the t-stat will not work right, and also the system will be airlocked and won't circulate.

[jeffcoslacker]

Originally Posted by Schurkey

Is it actually overheating, or are you blowing compression pressure into the cooling system through a non-sealing head gasket or a cracked casting?

What temperature is the coolant; and how are you measuring that temperature?

Yeah blowing hoses off sounds suspicious.

A healthy, stone cold motor will usually start to show heat in the hoses long before pressure after running for a few minutes....whenever I note that the hoses are blowing up tight within a couple of minutes and long before heat starts to appear in them, I wonder about compression to cooling jacket leak...

But air expands a lot more than coolant, so it can also indicate a large presence of air in the system...sometimes while bleeding them running, you find that they never stop blowing air bubbles from the bleeders...not a good sign. Bubbles venting to the reservoir at regular intervals while running, and increasing in step with raised rpms is bad news too...

[DrgnLdyLizHicks]

So how do I fix it? It's been sitting in the parking lot of Walmart where I work for two weeks as of today. I can limp it up the street to a mechanic, but as of right now, I don't have enough money to pay for repairs.

The temp on the dash is where it says it's overheating. What can I do?

This car is making me . Too bad there isn't an emoticon for ripping out your hair.

It's not doing the air bubble thing. If we bleed while running, eventually the bubbles stop, and there are no air bubbles coming into the reservoir. As far as we can tell, the coolant IS circulating. My husband thinks the cooling sensor is bad. Is this possible?

[WyrTwister]

Originally Posted by DrgnLdyLizHicks

So how do I fix it? It's been sitting in the parking lot of Walmart where I work for two weeks as of today. I can limp it up the street to a mechanic, but as of right now, I don't have enough money to pay for repairs.

The temp on the dash is where it says it's overheating. What can I do?

This car is making me . Too bad there isn't an emoticon for ripping out your hair.

It's not doing the air bubble thing. If we bleed while running, eventually the bubbles stop, and there are no air bubbles coming into the reservoir. As far as we can tell, the coolant IS circulating. My husband thinks the cooling sensor is bad. Is this possible?

First , bleed / burp the air out with the radiator cap off . Second , my 96 Lumina 3.1L has a " vent " in the fitting where the driver's side radiator hose attaches ( thermostat is at the opposite end of the fitting ) . Try bleeding / burping it there also .

With that vent closed and the radiator cap off , if it never quits burping , you may have compression gasses leaking into the radiator ?

In any event , you may be able to get it to limp home with the radiator cap off ?

The older cars , it was possible the thermostat up side down . If you did that , the thermostat would not open right . Do not know if the Lumina thermostat will fit upside down ?

As far as the fans , there are 2 , if I remember . Normally one comes on . I think the second comes on if the first one is not sufficient .

I seem to remember , both come on when you turn the A/C on .

The fans each have their own relay . The relays are controlled by the computer . The computer decides when to turn them on , based on the engine temperature .

Check the relays . This time of year , winter , only one fan should be needed . I think both relays are the same ? Try swapping them , maybe one is defective ?

I doubt they are expensive ? Might buy one , to trouble shoot , if you have to ?

Also , the fan motors may be going out ?

I am thinking , you need to determine if it is a fan / electrical problem . Or a coolant circulation problem . Or a radiator problem . Or a compression leaking into the cooling system problem ?

God bless
Wyr