hi, i have a 2006 tacoma with a 2.7 liter and 225,000 miles this week the overflow tank started filling up. doesnt run hot so i changed thermostat and radiator cap problem continued. replace water pump and fan clutch flushed system and problem continues. no white smoke no antifreeze on oil dip stick need help with thoughts or similar issues and solution. thanks
anti freeze filling up over flow tank
- Thread starter joemrmold
- Start date
Demo Man
Well-Known Member
If it's not running hot your ok. That's why they call it an overflow tank.
demo thanks for your reply. a little more info, it overflow the overflow and if i dont fill radiator it will get hot any other thought? thanks
Demo Man
Well-Known Member
Ok. I'm not insulting you by asking this. Did you put the right radiator cap on? Are you filling the overflow tank to the top instead of the cold/hot line?
Your building up pressure somewhere. You (might) have a small crack in your head gasket somewhere. Are you the original owner? Has the head gasket been replaced?
taco cruiser
Well-Known Member
I personally wait till truck is cold.. I would first put a pressure test on the radiator pump up the pressure to 18lbs and make sure it stays at the pressure of 18lbs. if it stays at pressure of 18l bs and does not bleed down that's a good sign. If it stays at that pressure I would use a burper on the radiator to fill it up the radiator ( burping helps get any air pockets in engine up to escape. After a complete burping fill the overflow up to recommended lvl. Start the engine and let the temp go to normal op temp. When the thermostat opens You should see the water circulating. If it has a strong circulation it is working correctly. If it barely bubbles then may be a weak water pump. Now after doing all that. If it continues to overheat i would def go along with previous poster and say you have a broken head gasket and the exaust is heating the antifreeze up and will require a new head gasket. However if the 1st test bleeds down it is a good sign that head gasket is shot but will also show any leaks anywhere else.. I hope I didn't confuse you but those are the tests I would run first. Could be a simple air pocket or a loose hose clamp and hopefully not be a head gasket. Good luck.. And keep me posted on your situation.
2016 Tacoma Trd Off-road. (Silver Bullet)
2015 Tacoma Sr5. (Polar Bear)
2016 Tacoma Trd Off-road. (Silver Bullet)
2015 Tacoma Sr5. (Polar Bear)
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thank you for your replies. ok here where were at. every morning i fill the radiator, start the car and let if warm up with the cap off. once the antifreeze come to the top. i close it up. heat work fine as i have a new thermostat that is installed correctly. i drive 1 hour to work. when i get to work the overflow tank, which i leave empty is full. after it cools down i empty the overflow and put the antifreeze back in the radiator. i am the original owner and have never done a head gasket. the car doesn't run hot, but if i let the antifreeze keep boiling over, i'm sure it will as now the radiator is down a few quarts. there are no signs of leaks and so far i have flushed the system with water only and the fluid coming out was clean. i changed the water pump and the fan clutch the thermostat and radiator cap. i dont have a pressure tester to put on the small neck of this radiator. i cant see in the radiaotor to check flow but i would think if it was clooged i would run hot? any other thoughts are appreciated. i was thinking of pulling the thermostat to see if i get better results but with winter coming i need heat. lol think it might be a head gasket but im in denial and hoping it something else. i
the coolant in the overflow tank should should be drawn back into the radiator when the truck cools. you have a leak in the line, or in one of the caps or fittings, that is allowing the radiator to draw air back in instead of the coolant in the overflow. it is probably the hose from the overflow tank to the radiator that has a pinhole leak.
mr_mumbles
New Member
I say the water pump you installed is faulty and would return it try another one I would say head gasket but after reading and re-reading your posts start at the beginning and replace water pump again if it does not fix the issue prepare to tear the engine down and replace the gaskets. I wish I could help out more but seems I would start at the source. Seeing as water pump was replaced it was replaced for a reason. It was overheating so that tells me head gasket. However I have purchased bad water pumps right out the box before. Stranger things have happened. SO sorry and good luck.