oil change


New Member
hi guys,

have a strange query here. somr time ago, i over filled my header tank a little, for months, the tank has been half full when cold and full to the top when hot and the car hasent used any water or blown this out. I did an oil change on the car yesterday and have taken the car for a few runs since hot and cold, and the water level has actually cond down to the max mark 1/3rd way up header) - even when hot.

Any ideas why this would happen? - is it becauyse the engines now running cooler (even though it dosent show on the water temp or oil gauges.

Any ideas.




Staff member
No. That defies logic, but it doesn't mean there's anything wrong. - I would have thought that it's more likely you managed to tip some out when you were doing the oil change.

I wouldn't stress about it if none of your gauges are showing it's getting hot. - My resevoir is always about 1/3rd full since I put a new cap on the radiator; if I top it up it will be about a 1/3rd full next time I check it, so I've stopped bothering. With the old cap that looked like it had perished seals, the level went up and down.

As for running cooler, how would it be doing that? - The oil is cooled by the radiator anyway (there's a heat exchanger on the back of the block).

It shouldn't be able to fill to the top; it should overflow before then. - Maybe the overflow was blocked and now it isn't?