Dedwards

Hey guys so my Lexus started over heating day before yesterday.... It is kicking out the hot coolant back into the overflow tank then just shoots steam. Fans turn on.... I replaced thermostat thinking old one was stuck.... Ran well for first 20 min then started steaming again ..... Not sure where to go from here..... I'm still learning!

nsghtbrwry

If the system was properly bled, I figure you either have a bad radiator cap, or a blown head gasket.

Dedwards

there is no coolant in my oil haven't tried the cap yet I think that is my next choice.... How do I bled the coolant system? Thanks for your help I'm still learning

nsghtbrwry

If it's the cap you will usually have sprayed coolant residue around the cap. Coolant won't always mix with oil when you blow a head gasket.

These cars are pretty easy to bleed, but if you were driving around and the coolant level in the reservoir never dropped, and now it's overheating, I don't think it's a problem with trapped air.

I use a spill-free funnel and dump in as much coolant as will go through the water outlet (where the radiator cap goes). I then squeeze the lower and upper radiator hoses and that gets some bubbles out and more coolant in. When no more goes in, I cap the system and fill the reservoir to the FULL mark. Then drive around with the heater on maximum until you get really hot air (then you can turn off the heater/close the heater valve). Check level and top off to FULL before you do each cold start. Usually takes two drives to bleed completely.

Do some research on other things to check for a BHG. AutoZone will rent you the chemical color-changing tester for free (refundable deposit).