A/C system questions (4000q)

[ejfluhr@austin.ibm.com (Fluhr)]

I am looking into an '86 4000q for sale for $2500 obo.  From talking with
the owner, the biggest problem is the broken A/C.  He has owned the car for
17 months, and bought it without working A/C.  He says he "runs the
compressor" (I assume by flipping the switch on the 4Kq A/C panel) fairly
often to keep it lubricated.  So, I have some questions about the A/C
system.

1)  If there is no freon in the system (I am assuming it has leaked out),
will the compressor operate when the A/C button is pressed?  If so, is
this kind of operation enough to keep it in decent shape for long periods
of time?

2)  It is possible the A/C system has not worked for several years.  What
damage or problems can occur to the system in this time period?  Corrosion
in the system?  Dried up seals/hoses?

3)  I have heard that the Coupe GT/4Kq uses a York compressor.  How robust
is this unit?  Can it be converted to R-134a by just changing the oil? 

4)  Do the hoses on the 4Kq need to be replaced with barrier hoses if I
switch to R-134a?  Any other changes (aside from the receiver/dryer and
adapter fittings) that need to be done to convert to R-134a?

5)  $2500 seems like a lot for a 4Kq without working A/C (broken odometer
also...the owner thinks 120+K miles).  How much should I estimate the
repair cost at if I want to deduct it from his asking price?  I would do
as much of the work myself as possible, but might have to pay to have the
system evacuated and recharged.

I know that EC did an R-134a conversion on their Project 4000q, and I
am trying to get a copy of that article.  However, they replaced the
compressor and hoses, if I remember correctly.  My goal would be to spend
the minimum necessary to get a reliable, working system, hence the desire
to retrofit the compressor.  

Thanks,
Eric
'85 Coupe GT
---
Eric J. Fluhr                                Email:  ejfluhr@austin.ibm.com
630FP Logic/Circuit Design                   Phone:  (512) 838-7589
IBM Server Group                             Austin, TX