I just changed the water pump, thermostat, and flushed the heater core. I ran the car for a while with the surge tank cover off and kept filling it. As soon as I got on th e-way it overheated.

I'm pasting a solution I posted from another similar overheat problem. Essentially the early equinox's had a few specific tasks that must me followed to the letter or you will not have good result once the cooling system is breeched. [Paste follows]

I had a similar problem with our second 2005 Equinox. If the heater core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove the plug, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. If you skip this step, you will have air in your system that creates hot spots. Fill the surge tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, Do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

I had a similar problem with our second 2005 Equinox. If the core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove it, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. Fill the tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

I think you are trying to bleed the radiator. I have pasted an earlier post regarding a similar cooling system issue. I hope this helps.


I had a similar problem with our second 2005 Equinox. If the core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove it, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. Fill the tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

There is a very specific coolant replacement procedure for the 2005, 6 Equinox. Below is a paste from another answer related to the cooling system that may help. Look for the refill procedure, but perhaps a full flush, as be in order as well.


I had a similar problem with our second 2005 Equinox. If the core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove it, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. Fill the tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

No, but I've pasted an earlier post that may help. The 2005, 6 cooling systems require a certain refill procedure. Please read down to the section you need. I hope this helps.



I had a similar problem with our second 2005 Equinox. If the core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove it, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. Fill the tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

I am pasting a related earlier post to cover most cooling system issues. Hopefully this helps.



I had a similar problem with our second 2005 Equinox. If the core is clogged, a proper flush is done by hooking garden hose adapters to both heater hoses and reversing the flow numerous times until all debris stops coming from it. Hook the hoses up again and perform a proper and complete system flush with the thermostat removed from the engine. My GM service manual suggests changing the thermostat after the complete system flush is done.
In our case, I put a flush attachment in line with the hose line that feeds the bottom of the surge tank and opened the drain plug on the bottom of the drivers side of the radiator. If you remove it, and nothing flows, use a firm yet still flexible long piece of thin round plastic to probe around the entry point until you break through the hardened sludge in there. You cannot send the probe straight in as there is a support inside of the port, probe at an angle until through. Flush very thoroughly and be patient to get it all out. Done correctly, you won't have to do it again for 150 k miles. Remember to replace the thermostat.
Important when filling, place in park, set the hand brake and chock wheels. Jack the forward right side of the car at that jacking point about 2 to 3 inches to orient the engine correctly to remove air from the system. Open the air bleed screw at the top of the water pump tower to let air bleed while you pour the correct orange Dexcool and water 50/50 mix into the surge tank. Once the air turns to steady flow of coolant with no spitting or bubbles from the tower, snug the screw down, but don't over tighten. You can lower the car at this point. Fill the tank to an inch above the seam halfway up inside of the tank, close the surge tank cap and start the car with the heater on full blast until the water has heated the surge tank very warm to the touch. Turn the engine off and wait for the engine to cool. Carefully remove the surge cap, very slowly to allow pressurized air to bleed, do not open while hot- ever!
Add more 50/50 mix of Dexcool to an inch above the inside seam of the tank. The service manual calls this process thermal cycling to remove all air pockets that remain. You are done with this process when you no longer have to add coolant to cover the inside tank seam after engine cool down.
Finally, and just as importantly, get cooling system sealing pellets from any GM dealer and the next time the engine is cool, drop all 5 pellets in the surge tank. They can be crushed before putting in the tank but I think dropping them in whole allows for a better and smoother application throughout the cooling system that avoids clogging the heater core. If you don't use these pellets after a coolant flush and change, your engine will weep coolant out of the head gasket near the #1 cylinder and will weep into the #1 cylinder. Pressurized hot gases will also leech into your water jacket at this same point which will promote solids forming in your coolant.
This whole process is pretty tedious but worth it in the long run. After I cured all of the cooling system issues with our car, I've come to really appreciate the darned good engineering that went into the drivetrain of the Equinox. Most of the problems in our car were caused by folks not following the rules when servicing the cooling system but while getting this worked out, I've picked up a good understanding of the modern fully closed high pressure GM cooling system. Best of luck!

A bad cap will definately cause your problem. Put a new radiator cap on and your problem should be gone. The cap controls the pressure in your system (usually about 15 lbs) and for every pound of the pressure the boiling point of your coolant goes up by 4-6 degrees.

These Tauruses had a problem with the heater cores plugging up, blowing out the head gaskets and no heat issues. Ford issued a TSB#98B26 (Tech Service Bulletin) to modify water pump and install a heater hose bypass tube. I would start by completely flushing the system with a good flush. Then reverse flushing the heater core. Refill the system and add a good additive. Also you can install the heater bypass tube as described in the TSB. The last one I did ran around $90 and 2 hours labor. Hope this helps you out.......

This happens ALL THE TIME!! Heater core is likely plugged with rust, yes. but a garden hose fix will NOT last. and the reserve probably IS cracked on bottom, as most are.They are relatively cheap from Ford, though. Have a REPUTABLE radiator shop do a Genuine Power Flush to the entire cooling system (not an automated fluid exchange many shops claim to be a "flush") and THEN have them unplug the heater in a similar fasion. Now is the time to replace the surge tank (old one is packed with rusty sediment that is usually partially plugging the cracks in it, and not very cost effective to clean anyway). On older, very rusty 2 valve 3.0 systems only other issues are the rear of timing cover gasket often leaks a little, and the water pump impellers can become eroded away (from rust) and water flow suffers. So... watch for residue or dripping from behind water pump. If minimal, a mild leak sealant added to a properly cleaned system with refill and tightening the bolts near leak will do the trick--otherwise timing cover gasket and pump replacement is needed.