STV's don't appear to have been used on the 4th Gen Maxima. I think they
were used on the '85 - '87 300ZX. Max's use TXV Thermal expansion valves.

"Steve T" <fotocord (AT) yahoo (DOT) com> wrote

Jim G wrote:

They were used on some model maximas and Z32's as well. This valve was used
along with an expansion valve. When they stick open, they produce the
problem you described. I'm glad your model doesn't use this, guess they
went back to electrically cycling the compressor to control the evap temp?
--

Steve

http://www.atlantaracing.com

Jim:

With respect to the oil quantity: What the nissan service manual
recommends is to measure how much oil is left in the old compressor and
put the same amount in the new compressor. Since you have no leaks, you
should not have lost any oil, so the rest of the oil, not in the
compressor is probably in the condenser etc.

With respect to the vacuum pump. I bought a 5 cfm (probably too big)
for $160 shipped to my door, It is a Robinair 15500. You would probably
be ok with a 15150 (1.5 cfm) or 15300 (3cfm) pump. I bought it from
Washer Specialties Co. 800-835-1010. Ask for the person in charge of
internet sales. If you are anywhere near southeast FL, you can use mine.

The best two ways to charge a system are by refrigerant weight or using
the sight glass (if equipped).

I think it is very unlikely that all the components you mention were
defective all defective at the same time. What were the pressure
readings? Temperatures of the refrigerant lines? Was the problem not
related to the heater core doors stuck in the heat position? Sometimes
the receiver drier gets blocked and you will have the problem you
experienced, case in which you will see a temp difference between the
two lines connected to the drier. If the TXV closes, the compressor
readings may appear as if the compressor was defective. Most A/C
service manuals have typical pressure and temperature readings for
different system problems. I could scan and email you one if interested.

In any case, good luck.

Jim G wrote:

I have a 96 GLE and the compressor just started cycling on then
switching right off again and this repeats about every 10 seconds. Some
old guy at a station in tow hooked some gauges on it and said that it
seemed liked the system was blocked. He said that since the dryer was
cheapest we should change that and if that didn't fix problem we should
replace the evaporator. Does this seem reasonable?

Mike (AT) ripleyhomeplace (DOT) com



AS wrote:

Mike:

It does not sound reasonable to me.

The reason for cycling on and off will most likely be, in my opinion,
that the system is low in refrigerant. $30 bucks spent at the autoparts
in buying the refrigerant and the charging hose should suffice to fix
your problem. The charging hose comes with instructions.

To check the dryer, just feel the temperature in both pipes that get to
the dryer itself. There should not be any noticeable temp. difference
when touching it by hand. The system would have to run for at least a
few minutes for this problem to be noticeable.

Never heard of a blocked evaporator, unless it was blocked to air
circulation (not refrigerant).

What normally blocks a system would be a defective or frozen expansion
valve or a clogged orifice.

Has the A/C system been worked on? Why would it block by itself?

Good luck

mike (AT) ripleyhomeplace (DOT) com wrote: