change coolant A4 B8 2.0 TFSI

[nearlydun]

Hi all, I am completely new to this so please be gentle.

I am repairing a crash damaged A4 B8 2.0 TFSI and this involves replacing the radiator pack which I have done.
I am now attempting to replace the coolant with G13 and have filled the expansion tank with tap water first to try and flush the system, however having got engine to around 90 degrees and squeezing hoses it does'nt seem to be circulating.
Can anyone give me a step by step idiots guide to flushing the coolant system and replacing coolant ensuring all air is purged?

Any help would be most appreciated

[Alan02]

If you pull one of the heater hoses back a little (by bulkhead), you will see a small bleed hole .

[niall campbell]

rule of thumb is to put heater on full blast, switch air con off ( probally ECON mode ) , put heater to the hottest setting and let car idle for 10 minutes

[nearlydun]

If you pull one of the heater hoses back a little (by bulkhead), you will see a small bleed hole .

Many thanks for taking the time to reply Alan.

I was'nt sure if my car had this breather. Do you know of this is the only breather that is fitted to a 2.0 TFSI 2009 (CDNC Engine code).

Also do you know how to dump all of the fluid out of the cooling system before refilling with new G13?

I tried filling the expansion tank with water and getting the engine up to temperature then removing the bottom hose from the rad but all that seemed to come out was the tap water I have put in and not any of the old green coolant that was originally in the car.

I want to try and get all of the old coolant out as the new coolant is G13 reddish purple and I have read somewhere that you should'nt mix the coolant as this could cause a reaction that would lead to the coolant solidifying.

Once again many thanks for your reply any further guidance would be greatly appreciated.

Neil

[nearlydun]

Hi Niall
Many thanks for your help and thanks for taking the time to reply.
I am going to have another go this afternoon. I did have the heater on full when I tried to change the fluid on the last attempt but I cant seem to get the water I have added to circulate as I think there could be an air lock. As per the previous reply by Alan, I am going to have another go and open up the breather to try and get the water to circulate and then dump all of the old coolant / water out by the bottom hose before refilling with new G13.

[niall campbell]

when you fill the car up with water / coolant, you have to wait until the car reaches 90 degrees on the dashboard before the water will circulate ................... this means the thermostat is fully open and the coolant is circulating right round the car, this includes the heater matrix

If I was you , get the car up to temp, slacken off the bottom radiator hose and drain, without burning yourself

As the car cools down, unhook one of the hoses into the bulkhead, and put a garden hose in and flush out the coolant in the heater matrix

Put in your new G13 coolant & make it a 50 % mix if not already done so