Air In The Cooling System !

[richardr42]

Hi. Can anybody hep me. I thought I had a radiator bockage and have now boughta new rad only to find the old one was okay but I have air in the system. The car runs happily all day upto 40mph (upto 1800 revs) but then overheats. Is there a secret in bleeding air out the system. When I talk people say its a tricky job on a LS400.

My car is a 93 LS400.

Please, somebody help?

[davepruce]

www.lexls.com is a really good site for tutorials and this page in particular may help you http://www.lexls.com/tutorials/cooling/coolant.html

[Rob]

shouldnt be too hard - is a bit better if the front of the car is facing slightly uphill,

when the engine is cold remove the rad cap, and start the engine ( i am not sure about the heater matrix if it is active or passive ie colloant goes thru it all the time or not so have the heater on max heat just in case, no need for the fan tho - using link above it is a passive system so you MUST have the heater on) have the coolant prepared and hopefully after a while the air will work its way out of the system, you might see this or the level will just drop a bit, keep doing this until the level stays constant - when finished check the coolant level on level ground and re install the rad cap and see what happens