Timing belt/water pump observations...

[AUDIDUDI@delphi.com]

FWIW, I recently did the timing belt/water pump/front crank seal, etc. on my
'89 200q and noticed something very interesting: not ONE of the timing marks
on the engine actually indicated TDC as the Bentley manual claims ... when I
double-checked everything using a pair of dial indicators (I had the oil pan
off so I measured off the No. 1 cylinder rod journal), I found that together
they were out of alignment by a little more than one-half a tooth on the cam
gear!  

Since the early-style cam gear has 44 teeth, this means that in order to fit
the timing belt onto the sprockets, you have to retard or advance the timing
by 4 degrees or more, which is enough to make a noticeable difference in how
the engine performs.  In the case of non-turbo engines, this will also alter
the ignition timing since the distributor is driven off the back of the cam,
which can compound the effect.

This is the first time I've ever checked the alignment this closely on an I5
motor so I don't know if mine is atypical but it's worth checking if you are
even mildly obsessive about performance.  :^)

As for the water pump, it may be possible to replace this without also doing
the timing belt on the 5ktqs but on my '89 200q, you have to remove the rear
timing belt cover in order to get the pump itself out and that means pulling
the timing belt and everything else in front of it.  Replacing the front oil
seal while you're in there is probably is a good idea as well...

     _             _             
    / l       l o l  \       l o   Jeffrey Goggin
   /__l l l / l l l  l l l / l l   * * * * * * *
  /   l l_l \_l l l__/ l_l \_l l   AudiDudi@delphi.com