Re: Hose diagram assembly

Posted by HH56 On 2017/4/30 23:46:36

The heater core has most likely sprung a leak and will need to be repaired by a radiator shop.

For a workaround on your car you will have to drain some of the coolant -- probably a couple of gallons -- to get the level below the heater outlet on the top of the head. Referring to Moms 54 photo, remove the long hose at the top tube on the heater that is coming from the water pump. Remove the short hose from the port on the head that is going to the thermostatic valve. Reconnect the long hose in its place making sure that it is fastened somwhere and cannot fall on the exhaust manifold. Once the long hose is connected you can pour the coolant back in. That will completely bypass the heater so you can still drive the car without leaks. Once it is bypassed then you can take your time in deciding when to have it repaired.

To remove the heater core is probably going to be a bit of a project. It is most likely a stock unit never worked on so in all probability there will be two sheet metal screws in the heater box cover inaccessable in back next to the firewall. Feel or use a mirror to look for the screws. They are at the same level as the screws on the front and side. If present, those back screws will prevent the box cover from separating and removing the core so the entire heater will have to be removed from the firewall.

To remove, start with taking the cable controlling the vent/heat flapper off at the side of the round tube where the coolant is coming from. Once it and the hoses are off the entire unit is held by 4 studs with nuts that must be removed from inside the car. They are under the large black square box directly above the air vent grille where the heater/defrost flapper is located. That box is held by some bent over tangs and I think maybe a screw. There is another cable which operates the heat/defrost flapper and may need to remove to allow it to come off. Once it is off you will see the nuts but if I remember correctly one is kind of a pain to get a wrench onto.

There are some photos of the heater installation in the accessories section of the service manual. When you have it fixed and go to replacing the heater on the firewall I suggest leaving the two back screws off so if there is a need to remove the core again you can just remove the side and front screws and lift the cover off.