Re: A/C questions 4K

[Jerry Croucher <croucher@mail.eos.net>]

Thanks to Steve & Phil for the help and comments about the AC on my
86 4kcsq.  As it turns out my system is working fine.  The cycling of
the radiator fan that I assumed was due to engine heat was the pressure
switch doing what it was supposed to do.  FWIW the fan comes on at
220 psi and goes off at 180 psi.  Next I will check the system for
dirt & clean if necessary the heater valve for proper operation.

Jerry

Sdthrl wrote:
> 
> You inquired about the A/C compressor/rad fan operation on your 4K and have
> had a little BTDT with my '86 4KCSQ.  As the other "lister" in California
> answered, the pressure switch is what operates the rad fan on my car as well.
> Here in the mid-west, A/C is pretty popular stuff and when I purchased my 4K,
> it was weak at best.  Now is OK, at best.  Never had it too cold in this car.
> 
> Your sight glass is under the top plastic cover for radiator ducting (two
> screws).  Also you will see the receiver/dryer (which I replaced) and the
> pressure switch located on the top of the receiver/dryer (which I should have
> replaced, it leaked).
> 
> Just for info, you might check the evaporator located behind the glove
> compartment.  When I removed the drip tray, I found the bottom surface of the
> fins about 80% clogged with lint, dust, whatever, effectively blocking air
> passage through the evaporator.  Cleaning this helped efficiency of the unit
> quite a bit.
> Operation of the A/C involves recirculated air from inside the passenger
> compartment and proper sealing and operation of the fresh air/recirc door
> located in the cowl area important.
> 
> One other thing, my heater control valve was leaking hot water constantly
> through the heater core in full cold position which drastically affected the
> temp of the A/C air.  The valve was $18 from the dealer.
> 
> Hope this helps.
> 
> Phil (Sdthrl)
> 4KCSQ  52K (each your heart out)
> 5KSQ  96K (only glass sunroof in the world)