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

Temperature Sensor Plug. Replacement radiators are generic for both Bosch and Reginaequipped
cars. Regina and some Bosch systems use a temperature sensor that fits into a hole
in the passenger side tank; it activates the electric fan. When you buy your replacement
radiator, make sure you ask for the rubber plug that fills the hole if your system does not use the
sensor. If your system uses the sensor, then ask for a new rubber seal to hold the sensor in
place. Remove the sensor by pulling it from the gasket. It uses no sealants and relies on a
friction fit. To install, first seat the gasket in the hole, them push in the sensor. It expands the
gasket to a tight fit. Liquid soap helps. Do not reuse the seal: install a new one if you remove it.
Procedure: To remove the radiator:
Tips:
● remove top support brackets and trim pieces
● remove electric fan and shroud if so equipped
● remove bottom airflow dam beneath the car which is screwed into the bottom of the
radiator
● remove automatic transmission coolant lines; not much oil will drain out, so use a cloth
under them to catch that which does
● disconnect and remove temperature sensor if installed
● disconnect lower and upper coolant hoses and reservoir hose
● disconnect air hose to reservoir from top left of radiator
● lift radiator out
● remove rubber supports on bottom and transfer to new radiator
● reverse the process for installation
● if your radiator has a coolant temperature sensor, use soapy water to install the rubber
seal with the sensor in the middle. Don't throw the box out before making sure you have
this seal.
● don't overtorque the hose clamps on plastic radiator connections or the coolant line nuts
● use a backup wrench when tightening coolant line nuts
● now is a great time to replace hoses and thermostat
● loosen the thermostat housing nuts to relieve trapped air when refilling
● [Mike Brown/Walt Posluszny] if the transmission cooler lines won't thread, take off the clip
that holds the two lines together back near the engine so that you have a little more
flexibility in lining up the fittings. Then put a little ATFon the threads to lubricate them and
move the trans line around with one hand to orient it 90 degrees to the fitting while
screwing in the fitting with your other hand. It takes some patience.
B6304 Engines. [Rafael Riverol] Don't look for an "all-metal" replacement radiator. You do not
want an all metal radiator in your 960/90 series car. You want a Volvo (Blackstone OEM) or
perhaps Nissens aluminum and plastic radiator to avoid bimetallic corrosion of the engine
through any voltage in the coolant, such as from bad grounds. You also want to put in new
Volvo coolant mixed 50/50 with distilled water.