Fwd: A/C system questions (4000q)

[Sandy Duffy <sandyduffy@home.com>]

You said:
>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.  

He can't "run the compressor" if there is no freon in the system.  It will
not operate.  There are two switches; that are low pressure and high
pressure cut outs (for safety reasons) that will prevent the operation of
the A/C in either condition exists.

>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?

See above

>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?

If the original fault of the system was a leak and not compressor failure,
the worst you will deal with is potential corrosion and dried out lines.
If the corrosion is bad enough, it will flake off and kill any new
compressor you install in the car within two to five hours of operation.
Dried out lines can go bad especially in the Texas heat.  I assume the car
has been there all its life?  
If the compressor failed, it might have injected bits of compressor vanes
into the entire A/C system.  In that case you will need a new evaporator
and evaporator OR a great warrantee program on the compressor from your A/C
dealer.  (This happened on my GMC pickup truck and on the fourth new
compressor (first three of them under warrantee) we finally purged the
system of old compressor bits)

>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? 

Can't help you here don't know enough about it.

>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?

Don't know enough

>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.

The broken odo would worry me but if you go ahead with the project I think
$1000. is the price to go with (compressor alone is like $700.00)

>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.  

That article is probably the best and least expensive way of getting a
reliable system IMHO.  Texas requires A/C.  If I lived there, I would
consider it a necessity.  You might get away a lot cheaper but my
experience with older non-functioning A/C units leads me to believe that
you will not.

HTH

Sandy