Water pump replacement

[treed2@u.washington.edu (T. Reed)]

Here's what you need to know about this job:

- definitely disconnect the battery before unbolting the alternator. i
  always forget this step and have ended up nearly welding tools to the
  nut on the alternator on accident (not to mention almost starting a fire)

- don't forget to drain the coolant (have new stuff on hand because the
  old will be dirty from dripping down all the hoses, chassis, etc)

- use only phosphate-free coolant (if you value your engine at all..
  otherwise all the aluminum parts (like the cylinder head, hmm) will
  dissolve in to the antifreeze and circulate as black puke in the
  coolant.)

- refill with 50/50 coolant and distilled water mix

- you'll want a set of sockets with allen bits in them. These make the job
  a lot easier because there are quite a few allen head bolts (a/c
  compressor pivot bolts, pulley bolts, etc) down in that area.
  Unfortunately it takes a little looking to find these in metric.
  Plain old allen keys will work but you'll cut up your nuckles and you'll
  probably need to put a cheater pipe on them.

- don't disconnect the a/c or power steering lines. just take the pumps
  off with the lines connected and set or "hang" them aside (with bent
  coat hanger wire)

- make sure you understand how the tensioning mechanisms work before you
  put everything back together and tighten the belts again. they're a
  little complicated and not quite what they seem at first sight.

- if you purchased a complete water pump your job will be easier. if not,
  you need to swap the pump in to the old housing. be very careful with
  the 6-8 bolts between the pump and the housing. They're literally famous
  for always snapping off.

- make sure the thermostat gets re-installed the correct direction.

- loosen the pulley bolts before removing the belts. otherwise the pulleys
  will just spin when you're trying to remove the bolts later.

- make sure you seat all the pulleys correctly on re-installation. They
  tend towards not seating properly.

- don't forget the two o-rings between the water pump and the block. if
  they're old it would be a good idea to replace them to prevent coolant
  leakage.

- when you start the car back up again, keep a very close eye on the
  temperature. chances are you will overheat if you just let it sit there
  because you will have an air bubble in your cooling system. the bubble
  sits right next to the thermostat, insulating it and preventing it from
  opening like it should. Some people drill a small hole in the thermostat
  to solve this problem. Others wedge an aspirin inside the thermostat to
  hold it open until the aspirin dissolves. The 'manual' method of burping
  the air out involves taking the reservoir cap off and running the engine
  at high rpms until the level in the reservoir drops waaaay down. Then
  add more water. Sometimes you need several heat and cool cycles too to
  get all the air out.

The hub size for the 16v water pump is 30mm.

Good luck,

-Toby

On Wed, 15 Jan 2003, der flo wrote:

> U wouldn't happen to know the hub size and how many bolts for the 16v one
> with p/s and a/c?  I called a auto parts store and there 4 different
> ones.
>
>
> On Wed, 15 Jan 2003 14:30:37 -0500 JoshuaA.Conner@VerizonWireless.com
> writes:
> > No AC: fairly easily, about 9 bolts.
> > With AC: small PITA b/c of the AC compressor
> >
> > My $.02
> > Joshua C.
> >
> > -----Original Message-----
> > From: der flo [mailto:derrickmd18@juno.com]
> > Sent: Wednesday, January 15, 2003 5:13 PM
> > To: scirocco-l@scirocco.org
> > Subject: Water pump replacement
> >
> >
> > How hard is it to replace the water pump on the 16v scirocco?
> >
>