Heater core O ring replacement

[bwitw]

Hi All,

I think I have to replace my heater core o-rings, as I have green fluid leaking into the footwell. I've read some great instructions online, but no-one mentions anything about radiator fluid levels. Do I need to drain the radiator fluid before changing the o-rings? Are the pipes normally full of fluid or air when the engine is off?

Any advice would be greatly appreciated.

[p38arover]

Yes. Full of coolant.

[PaulP38a]

to elaborate a little on Ron's response... yes, they are usually full of coolant. This is how I empty them... be careful and use protection.
After draining the radiator, disconnect one of the heater hoses going through the firewall on the engine side.
Clean the end of the hose with clean water first, then blow through it to push coolant in the hose and heater matrix out the other pipe.
There should not be much, if any coolant left low when you replace the heter core o-rings.
Cheers, Paul.

[wanglemoose]

when i did mine all i did was clamp the heater lines under the bonnet and put an ice cream container under the pipes in the car when i pulled them off, lost about 1 liter of coolant.
cheers
mick