Coolant levels after 1.9 1y conversion

[tonyandhelen]

Hi, I've had the original 1.6d engine replaced to a 1.9 1y the header tank is full to the brim, however very little water in the expansion tank. could anyone tell me if the expansion tank still needs to be filled to the full mark.many thanks

[marlinowner]

Ideally yes, there needs to be at least some coolant there when the engine is cold so there is no risk of air being sucked into the rest of the system. Saying that, there are people running with no expansion tank at all, with no obvious detriment. Probably less of a problem with a diesel engine as they are not so susceptible to internal corrosion which air in the cooling system might exacerbate.

[tonyandhelen]

Many thanks