Once I decided to go all out and tackle not just mechanical restoration of the MGA, but correctly painting the engine compartment etc. it was time to start disassembly. I knew I would likely be replacing all the soft lines and hoses and many other parts of the car. However, I also had to clear out almost everything in the engine compartment in order to strip and paint it the correct color. In addition, having that all cleared would make installing the new wiring harness easier.
The first thing I tackled was the heater box.
Removing the MGA heater box is pretty straight forward. The heater core, blower fan and air inlet and outlet ports are all one big assembly. There are only two water hoses connecting the unit to the engine. So I drained the radiator and commenced removing the heater hoses. These were in bad shape and certainly had to be discarded.
The heater is fixed onto the heater shelf by a ring of screws and there is a rubber gasket between the heater base and the heater shelf. You can count on replacing that. The connection between the dash air control and the heater air inlet can be released at the heater. The heater motor has power provided by two wires with quick disconnects located between the back of the heater and the front of the the bulkhead. Remember to undo these.
Beneath the dash there are two ports and cardboard hoses that direct air to the windscreen. These obviously have to be removed. However, I have also found that the aluminum outlet ports have to be removed from the heater box to get the unit free of the heater shelf. Once these are removed you can lift the heater free of the car. Be careful – it is relatively heavy and you do not want to dent the top of a fender getting it away from the car.
To wrap it all up – I was careful to remove the original build plate and patent plate and keep them in a safe place. These important and original parts of the car’s history can be replaced with reproduction one’s, but I had good originals that I obviously wanted to preserve. Off they came and away they went into storage.