BMW 5251 Service Manual page 521

170-25
Radiator and Cooling system]
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Disconnect expansion tank:
Remove expansion tank bleed screw and support clip (A)
Loosen hose clamp (6) and disconnect coolant hose from
expansion tank.
Disconnect harness connector from coolant level sensor
(C).
Push top of expansion tank toward engine and disconnect
bleed hose.
Lift expansion tank to free it from lower mounts, then lift
straight up to remove.
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Installation is reverse of removal, noting the following:
Fill radiator and cooling system as described earlier. See
Coolant, draining a n d filling (6-cylinder models) or
Coolant, draining a n d filling (V-8 models).