RE: heater core in a '87 5ktq

["Buchholz, Steven" <Steven.Buchholz@kla-tencor.com>]

Actually the heater core on the 5k is a bit easier than it can be on other
cars.  Unfortunately, it is somewhat of a learning experience, so the first
time is likely to be a PITA ... but the next time you'll find it to be quite
simple ... :-)
 
To do the heater core you have to pull out the HVAC blower box located under
the black plastic cover under the hood and behind the firewall.  Under the
hood, you'll find the blower box is held in place by a single strap, but you
will need to disconnect the cable to the blower motor, the bowden cable that
controls the regulating flaps, the coolant lines to the heater core as well
as a vacuum line that goes to the heater valve; and push back the corrugated
duct that goes from the right side of the blower box into the housing around
the A/C evaporator.  Inside the car you'll need to remove the lower dash
panels on both driver and passenger's sides to disconnect the plastic air
ducts that go to the footwell.  Remove the rubber piece that attaches the
blower box to the duct that goes under the console to the rear seats and
disconnect the vacuum lines from the programmer.  Memory's a bit fuzzy, but
I think there were in line connectors that allowed you to know which color
line went where ... or you might need to make up a diagram.  Now that
everything is loose you need to break the seal between the blower box and
the body of the car.  It takes some doing, but you need to lift the end of
the box nearest the firewall while sliding the back side forward.  This is
one of the two difficult stages of the process.
 
Now that the box is out you will find that the box has two halves which are
held together by a number of clips around the periphery and a number of
screws ... some of which are deep within recesses in the plastic and
difficult to see.  Once the halves are split it will be fairly obvious how
the heater core is replaced ... just be sure that the fittings are in the
same orientation as the old core.  It is also recommended that you replace
the blower motor if you don't know how long the current one has been in
place.  Reassembly of the blower box is the second difficult stage of the
process.  The problem is getting all the blasted flaps to line up properly
as the box is assembled.  There is an Audi part for a tool that holds the
flaps in place for reassembly ... I wish I had one so that I could post a
1:1 diagram of the dimensions on a website.  Having the tool turns this
phase into a simple job.  I'm sure the tool could easily be made from
cardboard ... perhaps you could make one before attempting to reassemble the
halves.  As the two halves come together you simply slide the tool out and
then reinstall the screws and clips.  Slide the blower box back into the car
and hook it back up.  I bought a roll of open cell foam insulation with
adhesive on one side to seal the heater core and blower box back to the car
body.  You might think about replacing the hoses to the heater core at this
time and the heater valve ... but they aren't that difficult to do at a
later time.  
 
BTW, you will most likely find a tremendous variation in prices for the
heater core ... shop around until you find one in the $40-75 range ...
 
HTH!
Steve Buchholz
San Jose, CA (USA)

-----Original Message-----



So the GF is taking the 88 5ktq on a little trip for the next week so i get
out old reliable this morning to drive to work, well looks like the heater
core is busted after warmup, coolant misting all in side the car and leaking
on the ground too :-(  So how big of a job is replacing the core, where can
i get one, and whats it going to cost me.
Thanks Guys!
Britt