Rad Flush

[Matts01ES]

Alright guy I have a 2004 alero 3.4 and it has time to perform a rad flush. But the problem is that I dont see is a rad cap. Am I wrong on this and just possibly blind? All I see is a tub that runs off the overflow bottle that connects to about 1/3 down on the left ride of the rad looking at the motor. I know to pull the plug at the bottom but what about putting water back in. Could you guys set me straight on this matter.

Thank you in advance.
Matt

[BNaylor]

Welcome to AF.

How many miles are your Alero and why do you want to do a cooling system flush so soon?

The plastic reservoir is pressurized and an integral part of the cooling system therefore not just an overflow reservoir like on other cars. You add coolant via the reservoir since there is no filler neck located on the radiator.

[Matts01ES]

just about 42k

and I notice that when I am sitting at a stop light the temp rises not enough to make a huge concern but enough to make u think that its time to change the fluid.

So since there isnt a filler neck on the rad. you have to put the fluid in the overflow to fill the rad? correct or is there another way?

[BNaylor]

It is normal to have the temperature rise even a little bit above the half mark on the temperature gauge especially during long idle periods. With the cooler weather the fans do not turn on right away because the A/C is not run as often. Without A/C on the fans will not start to turn on to cool the radiator until around 225 - 230 degrees.

When you add coolant it will all trickle down or gravity feed into the radiator.

I have around 43K miles on an '02 Alero GL2 with 3400 and the Dexcool coolant looks as good as new but its your choice as to whether you want to do the flush and add new coolant.

[Matts01ES]

When I first got the car it never went over the half way point and i have notice lately that is has been. Probably take a long time to refill the rad up with that method since there isnt a filler neck.

[BNaylor]

Actually it doesn't take that much longer. If you decide to flush and when resupplying coolant just leave the cap off. Start the engine up and let it do the work for you. As engine warms up continue adding coolant until it gets to the proper mark especially when the thermostat opens. Replace the cap and take it out for a test drive and then double check coolant level at the tank. Final step is to make sure there is no air in the cooling system. There is a bleeder valve located on the black tower located on the top of the water pump. Getting the car front end higher helps with bleeding. After a few days double check the coolant level just to be sure.

[MT-2500]

Originally Posted by Matts01ES

When I first got the car it never went over the half way point and i have notice lately that is has been. Probably take a long time to refill the rad up with that method since there isnt a filler neck.

Some of them are a pain to flush and get the air out.
Not saying you can not do it but sometimes it is better to take it to a repair shop with a flush machine.
Less mess and pain.
Have you been driving with the AC off lately?
Keep in mind that when the AC or defrost is on the cooling fan runs all of the time.
With them off the cooling fan only turns on when the engine tempt gets to around 220 degrees.
Try it with the AC or defrost on and see if rad fan runs all of the time and it goes back to normal tempt around 195-200 degrees.
Let us know how it goes.
MT

[Matts01ES]

Wow thanks guys for the advice