Genuine Audi 4000 Radiator

Audi 4000 Radiator Parts and Q&A

• Radiator
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  Q: How to disconnect the battery negative lead and drain the cooling system for radiator removal on Audi 4000?

  A:

  Disconnect the battery negative lead and drain the cooling system. For four-cylinder engines, on models with air conditioning, remove the front grille and detach the condenser from the radiator by removing the screws. Loosen the clips and disconnect the top and bottom hoses from the radiator, and where fitted, disconnect the expansion tank vent pipe and supply hose. Disconnect the wiring from the electric cooling fan and the thermo-switch, then unscrew and remove the mounting nuts and washers. Move the top of the radiator to the rear, unscrew and remove the upper bonded rubber mountings, then lift the radiator from the lower mountings and move it to one side, lifting it from the engine compartment along with the electric cooling fan and cowling. If necessary, unbolt the cooling fan and cowling from the radiator, then unscrew the nuts and separate the fan and motor from the cowling. For five-cylinder engines, unbolt and remove the upper radiator cowl, loosen the clips and disconnect the top and bottom hoses and the expansion tank vent hose from the radiator, and disconnect the wiring from the electric cooling fan and the thermo-switch. Remove the nuts and washers from the upper mountings and unbolt the upper mounting bracket. On models with air conditioning, cut the lower radiator cowl as necessary to thread the panel over the condenser hose, then unscrew the remaining mounting nut or cowl screws and lift out the radiator complete with the electric cooling fan and cowling. If needed, unbolt the cooling fan and cowling from the radiator, then unscrew the nuts and separate the fan and motor from the cowling. For all models, radiator repair is best left to a specialist, although minor leaks can be stopped using a proprietary coolant additive. Clear the radiator matrix of debris with a soft brush or by hosing, reverse flush the radiator, and renew the hoses and clips if damaged or deteriorated. Refitting is a reversal of removal, ensuring to fill the cooling system and fit a new sealing washer if the thermo-switch is removed.