[Ben125]

Engine over heated on my 2003 forester, 2l petrol AWD. Thermostat was changed and water still isnt circulating properly and engine is still overheating. any ideas whats wrong and what to do next? thanks

 

[Jinx Barker]

Engine over heated on my 2003 forester, 2l petrol AWD. Thermostat was changed and water still isnt circulating properly and engine is still overheating. any ideas whats wrong and what to do next? thanks

Thermostat was changed? Was it put in upside down?
(Trying to see the most simple problem first)
Also, did you make sure to check all the hoses and such for blockage?
And finally when you replaced the thermostat, you topped up the antifreeze and made sure it ran OK first?

 

[rsay777]

assuming that the t-stat was installed correctly then I would look at a partially blocked radiator or water pump not circulating.

you didn't mention if the fans are coming on. Rad cap not holding pressure. Head gaskets could be leaking exhaust into coolant.

 

[flstffxe]

The 2.0L almost never sees head gasket issues, so be fore condemning them I would look at a few other options.

Were there overheating issues before replacing the t-stat? What were they?

Things that could contribute to overheating:
-Air pocket in cooling system, as the system was just played with this would be a good place to start. Rebleed/burp the system to get the air out.

-plugged radiator, as mentioned above.

-fans not coming on, do they cycle?

-bad water pump? Also very rare.

 

[Ben125]

thermostat is definitley ok . water pump is working fine and the fans are coming on . But the engine is still overheating. Any more ideas? thanks

 

[flstffxe]

I would start to lean towards HGs considering what you say above, but I would have the coolant tested for hydrocarbons(exhaust gases), run a pressure test on the coolant system and possibly do a leak down test on the cylinders before condemning them. If one test points to bad HGs I would call it a day and see if replacing them is some thing you want to do.

 

[Ben125]

problem sorted , thankfully not the head gaskets. turned out to be a blocked radiator. thanks for the help