I am still experiencing problems with my 2000 s80 t6. there is a message on the dash saying coolant level low. i drained the coolant and only drained 1 1/2 gal. the manual says it takes 2 1/2 gal. i suspected the thermostat was faulty so i removed and tested it (boil test). the thermostat opened so i replaced it. i then filled the resivour tank and could only get in alittle over 1gal. after starting the car the temp went to half way, then alittle past, so i turned the car off (not wanting to do any damage) i noticed the top hose was hot, as expected, but the lower hose was cold. would you think the water pump needs replaced, or would there be a restriction somewhere? anybody have any ideas?

 

First off, if the coolant level in the expansion tank was proper, I would suspect that you had an electrical problem somewhere, like a loose or broken wire to the expansion tank. If the car was not overheating, I would not see the need to test the thermostat or suspect that the water pump was bad.

9 Times out of 10 a water pump will leak before they break. And a thermostat is suppose to open when it reaches a certain temperature, like 185 degrees.

When you drain the coolant system, it will not drain ALL of the fluid from the system, it's not a gas tank. There is fluid running throughout the motor and heater system that will not come out by simply opening the drain petcock. Then when you refill it through the expansion tank it will not fill all that was drained, you will have to run the motor several times and refill the expansion tank when the motor is cold before you get it back to it's proper level. As for the temp needle going a little past the 1/2 mark, I would suggest you drive the car a little because you may have an air pocket in there causing the higher reading which could go back down I a minute or two. Just don't let it overheat, get to high. Driving it a few miles will get any air out of the system.

 

I understand everything you are telling me. there seems to be a good electrical connection to the resivour but there is still a display showing on the dash concerning the coolant level being low. I forgot to mention that the upper hose is collapsed which would indicate the air being trapped, but even before i leave the driveway, the heat gauge is just past the middle after ideling for about 5 min. would you still drive the car and hope the air removes itself, then refill the resivour to the proper level?

 

Yes I would. I would also have a OBD-II reader connected to monitor the temp electroniclly and shut down before it gets over 250. One thing that bothers me is that you said the upper hose is collapsed. Is that hose old? The thermostat will have to open to get the trapped air out if there is trapped air.

It is possible that the water pump is broken. I had one broken in a 960 but that would never cause the coolant level light to come on. There is something else going on to cause that level light.

 

Yes, drive it around. That's the only thing that worked for me to get away from the red.

 

i have since replaced the thermostat with a volvo original equip one. Also, i drained the block of the engine from the drain on the back side of the engine, so im sure all of the fluid was removed. i also replaced the upper radiator hose, then refilled, and still can only squeeze in 1 1/2 gal of coolant.

 

Aprotec58, I would move forward on the assumption that the coolant level IS NOT LOW. Is the car over heating? Did you connect a OBD-II reader and check the temp? Do you still have a low coolant light? Are you sure all of the wires are connected good?