Hi, I have a 57 plate ST2 and have noticed that a small amount of coolant has started to be lost a regular intervals. If I top up to just above minimum reservoir line then 1 week later coolant will be 1 inch below this line when the engine is cold. No noticeable smells or leaks or colouration in oil or in coolant. When I look at coolant level after driving (so when engine is hot) it will be back up to minimum level (suggesting noticeable expansion of water between hot and cold). I'm starting to think that water expansion when hot has resulted in coolant discharge through reservoir overflow. I'm hoping I'm wrong! Presumably the only way to truly diagnose is through a compression test? If there is a gasket problem I could do with a recommendation as to where to go to get fixed?? (Based in London)
Many thanks.

 

Hi michael. I would also read up on cracked liners. Big problems on ST'S

 

Hi, thanks for the reply. Had a read on liners but seems more likely on tuned versions (mine's standard) or high mileage (mine's 30k). Also liner problem would show a symptom of ongoing loss of coolant, mine seems to stop after losing an inch in the reservoir.

 

No noticeable smoke from exhaust and no hesitation/misfire?

 

Funnily enough if I top mine up to the maximum mark it usually drops to half way between max and min within about 500 miles. But never drops lower. Never understood why it does it.

The liners failing is a big problem on 57-08 plate cars, it does give very similar symptoms to a failed head gasket.

 

Give one of these a go. If its negative, it could be something as simple as a slight water leak somewhere.

http://www.burtonpower.com/block-tes...t-jsbt500.html

 

The liners have been known to go on standard low mileage engines as well, its a lottery but if there's no misfire and no smoke/steam on start up I'd rule that out