Our 96 318 ti (70000k) started getting into the dangerously hot range on a motorway trip last week. When I lifted the bonnet I wasn't sure what i was looking at--I don't normally drive the car. What was obviously the radiator cap seems to be on the expansion or overflow tank. Anyway it took hardly any water. The problem didn't go away so we had it towed to our garage in town. They replaced thermostat and water pump and had the radiator tested.we were told some of the chambers (sic) were clogged couldn't be repaired needed to be replaced. Chambers? I've replaced radiators before and know they have a top and bottom tank, but don't know about chambers. Also there is a small screw cap near the radiator cap. What's that for? Any advice on the cooling system would be appreciated. Thanks.
radiator 
Linear Mode
