Well, I got the new radiator in (and its fully metal instead of half metal half plastic! no more broken necks!!!) but I have a couple more stupid questions though...

Since my existing upper hose has a split in it, it is going to be replaced. Since I went and put a new radiator in, and am gonna be putting a new upper hose in, I figured now would be as good a time as any for a really good coolant system flush and fill...

So first of all, any reccomendations on what to use as far as cleaning out the system and flushing it? As for the refil, I assume that any good ethylene glycol coolant is good... what about the 50/50 premix stuff? I figured I would just splice in a flush connector into the existing upper hose that is going to be replaced soon, so I dont have to cut up a brand new hose when I do the flush and fill...

Second stupid question.... It just dawned on me as I was pouring water in to the reservoir, that this is a completely sealed system... how the heck do I bleed the air out of it and fill the cooling system up? I really am smacking myself for not being able to figure this one out... but uhhh... how do ya do that?

Cheers
Jeff

its the same as on my 90. fill it up as far as it goes. then turn the car on with the heater on def full blast watch the coolant go down fill as needed. to flush i would use the advance auto parts brand coolant made for aluminum engines. then refill with the audi specified fluid just in case. my 85 book says that stuff is supposed to last forever without needing changed.

best way to flush the coolant is going to to unplug the big thick hose that goes to the thermostat... once drained from there, remove your bumper (its a lot easier than you think... only 2 hex bolts underneath and a few little trim things and the grill... maybe 15 minutes tops. There is an auxillary radiator down there thats mounted on either side - release one of the side mounts as well as the hose going to it... tilt the radiator to allow it to drain all of its coolant, rust etc. out. This part isn't a huge deal, but its a decent idea if it hasn't been done in a while.

Close up the hose clamps again, fill with your flush what have you as well as water and run it for a little while. I'm not sure whether driving it really is beneficial or not (it says to on the container).

Drain the flush what have you, run some water through the system and button everything back up.

Get g1100 coolant (made by pentosin, I think... used by audis and VWs)... get the "longtime" not the "lifetime"... its blue.

Fill as per the table on the side of container... fill up the resevoir until its full, then turn on your heat full blast, full heat setting and let the coolant flow through the system. Continue to fill until topped off.

If you really want to go all out, get a little funnel and fill the topmost line that connects to the resevoir - it will allow everything to fill up all the way opposed to the container which doesn't completely allow the top hose to fill.

I'd buy 3 1.5l jugs of the blue stuff - you probably won't need it all but its definitely good to have a spare since a lot of places don't carry it.

Have fun!

Andrew

Believe it or not, I ordered it from Autozone...

Actually, I didnt know it was gonna be all metal till I got it. I was just desperately in need of a radiator, and they happened to carry one for the 87 5K and could get it to me faster than I could get one from somewhere like Autohaus or Blau... Plus, being desperate and all, I was more than happy to pay them for it (it was about 190 plus tax).

When I got it though, I discovered it was all metal, which made the 190 well worth it to me... If I remember tomorrow, I will go find the packaging and get a part number and manufacturer for ya...

Jeff