Hello,

The best way to install the capillary tube is with the heater box removed, which is not that hard, even with the engine in place although not as easy as with the engine removed. It will take a while and you have to be very careful when removing the 2 nuts that hold the box to the firewall as I have had them break because of rust. There is a 3rd mounting bolt on top of the heater box that you have to access with the air intake grille removed(silver thing between the hood and windshield). Remove the heater hoses and the heater control cables from the heater box and heater valve. Pull down on the top of the heater box from inside the engine compartment and you might have to push up from the inside of the car to break the grip of the old mounting gaskets.

When you want to rebuild the heater box, all the mounting and sealing gaskets and drain hose are available new.

I have them in stock.

A bit of info I am pretty sure not many people know about the drain hose for the 122 and 1800 heater boxes and that there is a very important retaining sleeve for the drain hose that has to be retreived and then reused when doing a proper overhaul of the heater box. I have found this retaining sleeve loose inside the heater box

Another tip on heater cores and that is whenever you have the heater box apart(this also applies to most heater cores) that you take the time to take the heater core to a radiator shop and have them "rod" and clean the core and insist that they pull both tanks and inspect and replace if necessary the flap or rubber that forces the water to properly circulate through the heater core.

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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90501