vt how to bleed the air from the cooling system ?

[bazza13]

Time to move on people we've all got alot older since this started time to put it to rest

 

[damotheking]

ok just to confirm the coke bottle method ? seems like the way to go
id say the bleeder is the for when it is hot thats the only way to let all that damn air out

 

[wortus]

ok just to confirm the coke bottle method ? seems like the way to go
id say the bleeder is the for when it is hot thats the only way to let all that damn air out

I think you will get most if not all of the air out doing it with the engine cold. The fluid in the coke bottle will be higher than the bleeder valve. Make sure though that your heater tap is open when your filling it up. You could let the car warm up with the coke bottle in if you want to, it can't hurt however it you seal the coke bottle with electrical tape it will start to come off with the heat.

 

[graham7773]

Zeussy, thanks for that. Out with the coke bottle and in with the top hose section. Cheers

 

[wortus]

Seems someone had issues with trapped air untilthey bled the air out of the system!
http://forums.justcommodores.com.au...-1997-2002/154746-vt-overheating-problem.html

 

[jetboy]

Im gunna chuck two cents in here , as a mechanic for the last 25 odd yrs , you really only need to bleed the air out if you totally empty the motor of water ie ; a rebuild or a replacement motor that is totally dry . just chucking in a new thermostat or a radiator it is possible just to get away without bleeding the system , as it will self bleed , however it is not reccomended , some times you win , sumtimes you lose . Just bleed it an be safe , an make sure the heater is on . By the way i have the "tool":rockon::yahoo::spot on:

 

[wortus]

Im gunna chuck two cents in here , as a mechanic for the last 25 odd yrs , you really only need to bleed the air out if you totally empty the motor of water ie ; a rebuild or a replacement motor that is totally dry . just chucking in a new thermostat or a radiator it is possible just to get away without bleeding the system , as it will self bleed , however it is not reccomended , some times you win , sumtimes you lose . Just bleed it an be safe , an make sure the heater is on . By the way i have the "tool":rockon::yahoo::spot on:

Exactly, bleeding it, with the tool or equiv. is the correct method recommended by Holden.

 

[Brett_jjj]

Just serviced a VXV6 cooling system today,and there was no need to open the bleeder valve, and I didnt need a bottle either, and there was no trapped air or overheating issues.I dont know what else to say,If you have problems with overheating and trapped air with these cars cooling systems, then maybe you had better pay someone to do it for you as you are doing something wrong.

 

[wortus]

Just serviced a VXV6 cooling system today,and there was no need to open the bleeder valve, and I didnt need a bottle either, and there was no trapped air or overheating issues.I dont know what else to say,If you have problems with overheating and trapped air with these cars cooling systems, then maybe you had better pay someone to do it for you as you are doing something wrong.

Here go again, always right hey? If you didn't open the bleeder then how do you know there was no trapped air?

 

[Cheap6]

As with most things on cars there is more than one way to do things. You can bleed the system with or without opening the bleed screw and with or without using a funnel/tool, although some understanding is required for any method to be effective.

If you choose to bleed without opening the bleed screw the engine must be run until the thermostat opens. If this is not done air will remain trapped in a "bubble" at the high point between the thermostat and radiator (top hose) as there is no coolant flow through that section until the thermostat starts to open. Without the coolant flow air so trapped cannot be swept through to the radiator to escape through the filler neck.

You can bleed without the funnel/tool by opening the bleed screw with the engine running. The hydraulic head generated by the water pump will be sufficient to push air through the little hole in the thermostat, even with the thermostat shut, to escape at the bleed screw. Coolant flow in the top hose, per se, is not required i.e. the thermostat can stay shut.

With the funnel/tool you can bleed from the screw without running the engine, air being pushed through the hole in the thermostat as before, this time by the static head of the water in the funnel. The engine should still be run briefly to ensure that any air trapped in local high spots within the coolant passages inside the engine is swept through to end up at that bleed screw.

If using the funnel, you don't have to fill the funnel completely with coolant. Water will suffice, remaining stratified over the coolant. That avoids wasting coolant and is less messy when the funnel/tool is removed.

Do not remove the funnel/tool or switch off the engine (whichever is relevant to the method used) with the bleed screw open as that would allow air back into the system.