Originally Posted by Mr. Sinister
These might be stupid questions, but:
Do you have the right mixture of water + coolant?
Is the thermostat installed correctly?
Have you tested the thermostat to make sure it's not defective?
I use the Subaru Super Blue coolant premixed 50/50 (yes, it's expensive but the color blue is pretty
I tested the old thermostat on the stove, then eventually replaced it with a new genuine suby unit......spring in torwards the engine.
At this point no question is stupid. If vacuum filling doesn't work I'm just going to rip the heads off, have them pressure checked and replace the gaskets.
The only other thought I had today was of one of the banjo bolts on the turbo coolant lines were partially or fully blocked, I'm grabbin at straws now, .........getting the ol' engine hoist out soon, lol.