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Is this of any help?
http://www.allpar.com/fix/radiator-purge.html
There is no flow to or from the radiator...
I've already done the following....
replaced thermostat
replaced water pump
radiator rod out
block check for combustion gases
still.....nothing... anybody know about this car...?
Thanks!
I wonder if someone put your thermostat in backwards?
air in the line....I guess...flows now
Seems that the fan wants to stay running, once it kicks on...got a clue, please let me know
thanks!
GEEZ you must have had a boatload of air in there...maybe someone forgot to fill it at all? The pump sucks water up from the bottom of the radiator.
Heres what its doing now....
Got the flow ok, and after running the car, everything seams fine.... but..... the gauge says its hot, and it isnt, and the fan is staying on. I think the fan/gauge sensor is one in the same. Is that where you would go first.....?
Thanks
I will let you know how it turns out!
The car overheated for the 3rd time this morning. The first time the car overheated was after a very cold night (below 10 degrees F) and it occured within 15 minutes after letting the car warm up. I felt the top and bottom radiator hoses and they were cold. I also noticed that the car left a trail of coolant behind it.
I decided to replace the thermostat and water heater. I then refilled the system with coolant and water (estimated a 50/50 mix). The car started and ran fine for the next 2-3 days. Then one morning (after another night of below 10 degree F temps), the car overheated again. Once again, it occured about 15 minutes down the road after I let the car warm up.
This time I had the car towed to a garage. They said that they ran a pressure test and everything turned out fine. They refilled the coolant and away I went ($150 later). The car started and ran fine for about 6 days. During this time, there were some very cold nights so I thought the solution was that I did not have the correct concentration of coolant to water in the system. Problem solved!
Not quite. This morning, after SUB ZERO temperatures overnight, I went outside and warmed up the car. I got in after 10 minutes and drove for about 10 minutes down the road. I began to hear gurgling noises from behind the heater controls and I feared for the worst. My fears were confirmed when I began to notice the tell-tale symptoms of overheating. The heat began to get luke warm and the dummy TEMP light appeared. Frustrated, I pulled over and left the car on a the side of a small side-street. I looked in the snow under the car and saw coolant drips. When I pulled over, I could heat the coolant boiling in the overflow container. I went to open the hood and it was frozen shut. I then pulled the hood release lever quite hard and stretched the metal wire so I now cannot open the hood.
As I hope you can see, I would like to blow this vehicle up, but it has run so well for the short time that I have owned and it was a Florida car so there is not rust. Maybe that is the problem... it is just not used to Connecticut winters!
Anyway, I should note, if you have not already figured out, I chose not to garage this car. I can kick the Mazda Miata out of the garage for the winter, but I would rather not do that. I see other "older" cars driving on very cold mornings and I notice snow on their hoods and trunks so, I gather that "their" cars were out in the cold all night too. Why can this Buick not tolerate cold temps?
What can I do??
Thank you very much for your reply,
Chris.
the secondary cooling fan only comes on when the A/C is switched on. Lately, the secondary fan is coming on all the time even when the A/C is off and it is cool outside, and it stays on for 10-15 seconds after the engine is turned off. The temperature gauge is at about the same place it has always been. I checked the coolant level it is fine.
Don't seem to know what the problem is. Do i need to maybe change thermostat. Thanks for any assistance..........
marko
What could cause this.
If you don't see the fluid moving, the either the pump isn't pumping, the thermostat isn't opening (but you've said you replaced that) or slight possibly it is air-locked (although this would normally clear by itself).
If I had this problem and didn't have fluid moving, I would take out the thermostat completely (for diagnostic purposes). No fluid movement now....replace the waterpump.
There are many good tests for bad head gaskets. At most auto parts stores you should be able to buy a test kit that can detect carbon monoxide gases in your engine coolant.
>> advice: CHANGE YOUR OLD CRACKED SERPENTINE BELTS <<
I think a better test kit is the one that tests for CO in the coolant itself.
Also you can pressurize the cooling system, and then pull out a spark plug and see if there's coolant on the tip of it...that's a sure fire method.
I think you have the problem licked. Such fast and violent overheating really has to come from combustion leaks seems to me.
My problem is the radiator likes to overheat on warm days especially after a medium drive (30-40 mins)at 60-70 mph. The inside thermostat light will come on and if you slow down to 45-50 mph for awhile (when stopping isn't an option) it will cool down and the light will go off. Later, once it has been parked and completely cooled off and checked, the radiator will be extremely low AND the cap on the overflow container will be off (even though it was secure before the drive).
We've tried changing out the thermostat and it didn't make a difference. Asside from the overflow container cap blowing and spewing coolant when it gets too hot, I'm fairly sure there are no leaks.
I never drove it extensively enough with the original straight six in it to know if it always did this or just since having the 389 in it. The radiator is original and was not changed out when we switched engines.
Is it possible that with the larger engine the original radiator just isn't enough to keep it cool? Does it sound like a newer radiator would take care of it, or might there be another problem?
If you have high speed overheat that's a circulation issue; if you have low speed overheat that's a cooling fan issue); if you have an immediate rapid overheat from cold to warm in 5 mintues, that's usually a head gasket issue or a thermostat issue.
So it sounds like you have a circulation issue, which suggests a) a bigger radiator, b) correct shroud and c) probably a coolant overflow tank attachment.
For instance, it may take a combination of inputs to determine if the fans should be ON (one or both fans), and at what speed (off, slow, fast). Inputs could be temperature of the coolant fluid (the need to cool it), whether the air conditioner was on or not (provided extra cooling load, and the need to have high air flow for the airconditioner cooling), speed (perhaps the fans are turned off it is known to have enough air flow on it's own), etc.
If you get a set of schematics, you can usually figure out what is supposed to happen. Alternatively if someone has the service manuals for your specific model, that would tell you definitely what to fix.
Good luck.
The dash temp gage says about one notch below 200 degrees usually. When I put in a new coolant temp sensor last Aug., the temp sat right on the notch below 200. When I was chasing the idle problem, I put the old 3-wire CTS back in and it warms up to a little above the notch before 200. Sometimes gets more than half way to the 200 notch. Since they read differently, I assumed they also read the temp for the gage as well as gave ECM info. I thought about the new sensor may have kept the car running cooler by a few degrees but it lets a bunch of coolant out to swap back again. Based on that, I had two gages telling me roughly the same temp for the coolant, so I thought the temp gage is accurate. With either sensor in, the fans still always ran.
You should be able to send from your own dave8697@carspace.com
- You have two fuses that power all of this. The top box on the left is the main fuse (60A) that carries the high current that drives the fans themselves. The second fuse shown as the box top center (I think it's 10A), is the power for the control circuitry of the relays.
- The fans will be in one of three states. They will either both be OFF, they will both be ON running at low speed, or both be ON running at high speed.
- The way they make the fans run at low speed, is that they string them in series....let me explain. These fans are 12V fans, and when they are given 12V they will run at high speed. 12V on one lead of the fan and ground on the other lead of the fan, will give the fan motor 12V and it will run fast. If however you wired the fans differently, in that you put 12V on the lead of one fan, took the output of that fan and connected it to the input of the 2nd fan, and then took the output of the 2nd fan and connected to ground.....each fan would only get 6V of power. Hence with only 6V of power, a 12V fan will run at low speed. This changing of the circuitry as to whether the fan is given 12V or 6V, is achieved with switching provided by the 3 relays depicted in the middle of the schematic.
- Relay understanding#1. I don't know if you understand how a relay works, so a brief tutorial. A relay has two sides to it, a primary (or control) side....and a secondary side. The primary side is comprised of a relay coil, which when power is supplied to the coil it becomes energized and magnetically pulls a lever down. If you look in the center of the schematic on the left, there is a relay called Cooling Fan Relay #1. The leftmost circuit from B5 to B6 (a resistor and a coil symbol) show that primary circuit. S116 (which is fed from the 10A fuse at P107 top of page) provides the 12V power to the primary side of the relay at B5. When B6 is pulled to ground by the PCM (Powertrain control module) at the bottom of the page, that relay would then be energized. One common failure of relays on the primary side, is that the wire in the winding becomes burnt and breaks, and if this occurs then the relay won't energize anymore and the secondary will fail to connect.
- Relay understanding #2. The second part of the relay is the secondary side, which is nothing more than a set of higher current contact points. These contact points have a resting position (when the primary isn't energized), and a triggered position (when the primary IS energized). The drawing is always the resting (un-energized) position. Back to your schematic and looking at the Cooling Fan Relay#1, it shows that when the relay is at rest, the points are open and 30 does NOT connect to 87. The 12V comes down from the fuse and connects to 30, and IF the relay is energized, then 30 will connect to 87 and the 12 V will pass on thru and connect to the LH Cooling Fan Motor. Common relay failures on the secondary side are that the contact points become pitted or burnt, and will either never close together, or will stay welded together and never part when the relay is at rest.
- The two controls for all of this are the two connections at the bottom of the page from the PCM. There is a low speed Control, and a high speed control.
- When the low speed control goes to ground, Cooling fan relay#1 primary gets energized, connecting the secondary contacts which gives 12v to the LH Cooling Fan Motor as described before. If you follow the output of that fan motor lead, it goes up thru the secondary points non-energized) of the Series/Parallel Cooling Fan, and then over to the RH Cooling Fan Motor, and then the other side of the RH motor is at Ground. Both Fans would run at low speed since they would each only have 6 V on them.
- When the high speed control goes to ground, this energizes two relays simultaneously....The Series/Parallel Relay , and the High Speed Cooling Fan Relay . If you look at the secondary contacts of the Series/Parallel Relay you will see that the LH Cooling Fan motor lead will now be connected to Ground, which will result in the LH motor running at high speed since it has all 12V across it's leads. If you look at the secondary points on the High Speed Cooling Fan Relay, you will see that it will provide 12V to the RH Cooling Fan Motor, so that fan will run at full speed.
So now that we understand how your system is supposed to work, we can understand your symptoms and try to determine what might be causing the problem.As I understand your symptoms, you say that both fans are running at full speed....which is a pretty important clue. In order for your fans to both run at full speed, then all three relays have to be energized. Cooling Fan Relay#1 would have to be triggered and energized, because that is where LH Cooling Fan gets it's 12V from. Since you say the LH Cooling Fan is running highspeed, then you also know that the Series/Parallel Cooling Fan Relay must be energized, because that is what turns the LH fan from running half speed to full speed. Since the RH Motor is spinning full speed and it get's it's full speed 12v power from the High Speed Cooling Fan relay, that relay must be energized as well.
So what could be wrong? It is unlikely that you would have 3 relays all fail at the same time (like contact points were welded shut). It's possible, but highly unlikely. Therefore, the PowerTrain Control Module PCM must be sending the signals to energize the relays. Again, it does that by grounding the DK GRN wire on the left (thereby energizing the Cooling Fan Relay1), as well as the DK BLU wire on the right (thereby energizing the other two relays). You can verify this if you are somehow able to unplug these two wires, and see if your fans stop.
In order to troubleshoot why the PCM is calling for high speed fans, unless you have a scan tool that can send the commands they reference....you're going to need to take it somewhere to fix it. If you possibly have the logic for the PCM, we might be able to take this diagnostics a little further.
A couple things I would suggest looking at. First thing you should look at is whether an error code (Diagnostic Trouble Code) has been set. There's a little blurb that indicates that the PCM will enable engine cooling fans when certain DTC's are set. If you have an OBD reader, you can read the error codes and reset them. Some autoparts stores are reported to do that for you (free or nominal charge), and I have seen a reader outside Jiffy Lube for $15. I have my own personal one, so you might also be able to find someone who owns one themselves. Second thing I would check, is to see how is it that the Airconditioning circuit enables the cooling fans. It may be that there is a relay in the A/C circuitry that is bad, perhaps continually sending info to the PCM that the A/C is on when it's not.