Coolant Flush?

[BenMTL]

Don't you hate it when a simple job takes 3 times longer than it should?

All I wanted to do yesterday was to flush my coolant but hit many problems along the way;

1) Nipple on the lower radiator hose doesn't do anything....I turn it to the left (counter clock wise) 90 degree and pull out a little bit but nothing came out...Eventually had to just take off that whole hose but it made a mess Am I doing something wrong here? No B7 guide for this but in a b6 guide it says 1) turn left 90 degree 2) pull out a bit 3) then turn 90 degree and pull more. Maybe was I doing it wrong? If I wasn't, doesn't anyone know the part number for this thing? Want to replace it if its broken so I can easily flush my system in the future....Probably a whole assembly with 2 hoses because they seem crimped on there(?).

2) Is it true our engines hold 9 liters or 9.5 quarts (2.37 gallons) of coolant?? My manual says so but that seems like a lot. Of course that is a 50% mix of coolant and distilled water, but even after just pulling my lower radiator hose off only 3 liters came out (0.8 gallons) and my expansion tank was empty. Yes some remains in the block but 6 liters of it (66%)? Can I safely get more out by running my engine until it spits all of it out? I.e car running but lower rad hose still disconnected.

Thanks guys, really appreciate the help!!

[mtroxel]

Nipple on the lower radiator hose doesn't do anything....I turn it to the left (counter clock wise) 90 degree and pull out a little bit but nothing came out

Me too. I think that doesn't work on a lot of 2.0's here.

Can I safely get more out by running my engine until it spits all of it out? I.e car running but lower rad hose still disconnected.

I wouldn't.

1. How long do you want the trubo to spin with no coolant?
2. You're close to the point where the pump is just spinning in the air right now. I'm not sure it would work.
3. You run your water pump with no lubricant.

[allstock]

Was the expansion tank open when you opened the valve?

[BenMTL]

Me too. I think that doesn't work on a lot of 2.0's here.

Damn...What does everyone do? Just undo the hose completely like I did?

Was the expansion tank open when you opened the valve?

Yep, made sure of that. Except I didn't open the valve Had to take the hose completely off.

[b7_Andy]

I recently did a coolant flush on an E46 bimmer. BMW has a drain plug on the block that dumps most of the coolant out. It's pretty convenient... I was able to flush 80% of the coolant out of the 8.5 liter system. I'm going to be doing a coolant flush on my buddy's a4 1.8 and my 3.2 soon so I'm curious about doing the flush on Audi's system. Audi's don't have a drain plug on the block do they? I don't know how you're supposed to get any coolant out without draining the block. I've heard with Audi's that you're supposed to pull the coolant hose off the oil cooler and that may drain some more coolant... I haven't tried it yet. I hope someone that knows more about this will post up here.

[BenMTL]

I've heard with Audi's that you're supposed to pull the coolant hose off the oil cooler and that may drain some more coolant... I haven't tried it yet.

Don't know if you are "supposed" to do that because it makes a mess but yes, I guess it is the only way to get more than only the 33% that comes out the drain port or lower radiator hose completely off.

[wding2000]

In the past year, I did work three times related to cooling system.

The first time, I did a complete coolant flush, as the original turns brown after 6 years. I followed this DIY:
http://www.audizine.com/forum/showth...(the-easy-way)
I bought three gallons of DISTILLED water and drained and refilled three times to make sure to get much out of engine block and heater core. I believe 2.0 TFSI has coolant capacity of 7.5 liters, so poured in over 3 liters STRAIGHT coolant in the last step.

The second time, did it for coolant temp stat, and the third, oil cooler / filter housing gasket change. In both cases, I just drained coolant from tank to do the work,then filled w/ 50/50 - I believe only need 1 or 2 liters straight.

As for drain plug, by third time, probably I was a little careless, it was damaged and could not open to drain. I ended up just disconnect hose. As long as it does not leak, I will just leave it.

[wding2000]

By the way, I do not think it is a good idea to turn on engine with 1/2 or even 2/3 coolant in the system. Just fill w/ distilled water full, then run until operating temp to have t-stat open, and keep heater on to get heater core in circulation.

[BenMTL]

Exactly the info I needed....Thanks wding!

Seems like that dam drain nipple doesn't work on most of our cars....The part is ~$100 so I'll probably leave it as is and pull it off completely as well....

As for draining and filling, will just buy more distilled water to flush everything out and then just check with my coolant meter thing to what temperature it is protected to