RE:4000kq lifters

[Stephen Jenkins <sjenkins@spiretech.com>]

Damien,

	Before you go to the expense of lifters and their replacement you need
to decide if it is the lifters or the vacuum pump that is noisy.  If it
is the lifters try an oil detergent like "CD-2" with a fresh 20w-50
"Kendall" oil change and filter (preferrably OEM because "FRAM" only
keeps out puppy dogs, elephants, tree branches and large rocks but not
DIRT), run it for apx. 1000 miles then rechange oil and filter again
with "Kendall" 20w-50.  This procedure has worked to quiet the lifters
on several of my VW & Audi motors.  The reason I suggest "Kendall" is it
has a low parafin content, it is also a good choice if you have oil
consumption between changes, any older VW/Audi I have owned that
consumed oil would use 50-75% less oil when I used "Kendall" over any
other brand ie:"valvoline", "Castrol", etc.  If this doesn't work then
investigate lifter replacement.  As far as the brake vacuum pump goes,
it is outragously priced, the only source I have found is the dealer at
a cost of apx. $518.00.  There is also a fix I have used 2 times now
that is still working on my Quantum GL5 and a friends 4KCSQ, remove the
pump from the head, clean the pushrod and the opening in the side of the
head with solvent.  Now remove the screws that hold the pump together(be
very careful, there are small pieces that will come out, open it like a
clam shell) clean all of the dirty oil and crud from the face of the
plunger and the little spring loaded air valves.  Lubricate the face of
the plunger, pushrod, opening in the head and other pump internals with
"Mobil 1" synthetic motor oil or a PTFE product like "Slick 50". 
Reassemble the pump and re-install on the car and give it a try, worse
case scenario is it doesn't work and you need to get a replacement which
is where you started at.  NOTE! This disassembly of the brake vacuum
pump is not for the mechanically challenged, you need to make accurate
notation on how it came apart and where EVERYTHING goes to put it back
together.  Also do not start this project without alternative
transportaion or availability to another pump, just in case you
screw-up.  I found that getting a pump from the salvage yard (apx. $50
around here) and refurbishing it first and then swapping with the one on
the car was an easier way to go.  Hope this helps.

Stephen Jenkins
Portland, OR