Volvo Maintenance Hints for 7xx/9xx - Bill Garland's Nuclear ...

uns right off the windshield and into the intake, down onto the blower motor and then on the
floor. I had this problem on both my 745s. If this is your problem use the 3M WindowWeld tape
noted above on the window edge of the shield to keep the water from getting in. Before you
install this, clean off both surfaces with lacquer thinner.
Debris in Interior Air Plenum:
PITA to try to dissassemble the air box, but you might try removing the blower motor (which may
be trashed if the lower bearing has been running in water!). Blower is held in with 4 or 5 screws,
one electrical connector, ground lead, and there is a motor cooling air tube. Motor housing is
usually sealed with RTV to prevent any air leaks. To get it out, remove panel above passenger
feet, remove the right side hard panel, unplug and remove computer and the computer bracket.
You should now have enough space to get it out - 8mm nut driver on flex extension is helpful.
Remove the tube from the motor housing and inspect the lower bearing - any signs of water or
rust in there likely means lower bearing is trashed and motor will soon fail. Then use air nozzle
to blow in to the drain and force any debris/leaves out through the blower motor hole, or try
clearing with piece of coat hanger. Just be careful not to damage the A/C unit inside. Of course,
the air method may only move the debris away from the drain temporarily. [Editor's Note:]
Check that the blower motor mount in the air plenum is not cracked.
Front Footwell Vent Seals. See the FAQ section describing leaks at the seals behind the front
footwell vent panel covers. These can leak and soak the carpets.
Other Leak Sources: See the Body: Glass section for other sources of leaks.
Air Conditioning:
Air Conditioning System Maintenance. [Procedure from Rafael Riverol]
Recharge After Leaks. See the FAQ Section below for the correct procedure.
Basic A/C Operation Information and Safety Caveats. [Chris Herbst] A/C does differ between
RWD models, so it is important to relay the CORRECT information about which side of a
particular system the components are on. Don't up getting something backwards, or reading
high pressure on the low pressure side and overcharging (and exploding) a system. And
possibly getting hurt in the process. For these reasons, it is HIGHLY recommended that anyone
who is unsure of what kind of system they are working on, stops and either figures out what it is,
or abandons the job until they can figure it out. Also it would probably be good for people who
are confused about these differences, to STOP giving advice before someone destroys their A/
C or gets injured. This is a review of systems on the 740/ 940. The 940 information applies to
certain models as noted in the section labeled "940". Models are listed by vehicle model
because most of the confusion I have seen is primarily caused by people applying 240 TVX A/C