Coolant Kaboom, Need Help

["Alexander van Gerbig" <Audi_80@email.msn.com>]

    Finally got my act together and changed the thermostat and coolant.  I
got a fluid kit from Blau and it had 2x 1.5L bottle of Pentosin coolant,
blue to my amazement.  I drained the whole system, heat on, draied all
hoses, and everything possible.  I noticed the proper mixture for my 80 is
3.5L coolant and 3.5L water.  I only had 3.0L coolant, no biggie just a
little more water, a little less protection.  I filled her up with all the
coolant and then proceded to fill with water.  Only got 2/3 through 4L
bottle of water, figured the it would level out and I could fill after the
engine was running.  Started her up and waited, finally started to flow,
everything seemed fine, waiting for fans, and I notice the fluid is up
against the cap.  So I slowly loosened the cap and I got a little fluid
dribble.  Left the cap off to see what will happen.  Nothing more, but can't
add extra water, confusing?  Fans come on, all is well, turn off engine
without cap on and kabooom, fluid all over garage floor.  Doooh!
    After cleaning up I moved the car outside and closed up the garage so
the animals can't drink the deadly.  Why can't I finish filling the tank to
the proper amount?  What is causing the overflowing as well?  First time I
have done the coolant, what did I mess up?

Thanks!

Alexander van Gerbig
'88 Audi 80 -- Koni Yellows, G&M Springs
HÖR Technologies Sport Hydro Cam, K&N Filter
Borbet Type T, Dunlop SP9000 Sport

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