Omega Owners Forum

Chat Area => General Car Chat => Topic started by: 24_Valve on 17 September 2010, 01:29:17

Title: Cooling system - Self Bleeding, HOW??
Post by: 24_Valve on 17 September 2010, 01:29:17
I am quite used to messing around with cooling systems, draining, flushing, replacing rads, fans, switches etc.. everything I've had before the mig either had a bleed nipple, screw or required running with rad cap/pressure cap off (after a coolant change) whilst squeezing hoses & raising to operating temp to expel trapped air. I understand that the mig is a pressurized system and self bleeding, yet has a threaded plastic cap that does not bleed off? how exactly does the system bleed/expel trapped air??? I understand the plumbing but not the physics  ;)
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: feeutfo on 17 September 2010, 01:39:09
Trapped air ends up back in the expansion bottle, so just keep an eye on it for a couple of days after  and top up as needed. Simples. :y
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: Welung666 on 17 September 2010, 07:36:07
To bleed it from cold start the car with the cap off, let it warm up a bit then start squeezing the large radiator hoses. As the system tries to pressurise it forces the air back to the expansion bottle. So with a little squuzing help from you it self bleeds :y
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: TheBoy on 17 September 2010, 09:36:07
As others have said, it all bleeds back to reservoir.  The volumes of coolant and air doesn't change, just the location of them...
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: TheBoy on 17 September 2010, 09:42:06
As others have hinted, to be honest, just start the car up with cap off for a few mins.  Sometimes a bit of top host squeezing helps, not always necessary, and turn the a/c on and off a few times (so that both coolant paths are utilised for a few mins each).

It would appear the most common place for airlocks is the heater matrix, so ensure the heaters get nice and toasty.


I always manually check the coolant for a couple of days after, as it does sometimes drop as more air swaps place with coolant. Probably overkill, but I reckon better safe than sorry
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: 24_Valve on 18 September 2010, 13:34:28
Cheers guys  :y
Title: Re: Cooling system - Self Bleeding, HOW??
Post by: 2woody on 23 September 2010, 00:42:41
to arrange a cooling system to be self-bleeding, just place the reservoir at the top of the system, seemples.

actually, for many reasons, some cars haven't got this, which is when you need separate bleed points, etc.