Hi

 

I bought a car around 9 months ago and it began overheating while driving it home on day or purchase, 2 days later a garage diagnosed for and charged £955.58 to replace head gasket. ( later discovered I was lied to and only water pump had been changed,  I didn't confront garage as had no concrete evidence )

 

I recently replaced expansion tank as old one began leaking, the replacement is not new as I couldn't have waited for 1 week for the delivery of a new one as needed it asap.

 

So I put the replacement coolant bottle on but checked a few days later and the level seemed to drop ( put it down to maybe it was disposing of excess water) but checked again a week or so later and it was hovering around the minimum level.

 

I noticed which is odd, when looking at coolant from hot the level seems to be lower than it does when I check coolant from cold , why is this ? then when car been parked overnight for example and I check it seems a tiny bit higher level than when hot ?   but as I say, even when checking from cold the level still seems to be dropping slightly.

 

 

 

Can't find no leaks, already replaced several hoses from a leak a while ago which caused it to overheat but got to it on time thankfully

 

Rather than jump to a head gasket conclusion try changing the cap on the expansion cap. If it isn't holding the pressure it will stop the coolant circulating, causing hotspots and the coolant could boil at a lower temperature than it would when fully pressurised. Its a part often overlooked and should be changed regularly.

 

Good luck