[Juggernaut]

Bob, one more vote for an air pocket.

I drilled a small hole in my thermostat & installed it with the hole at the 12 o'clock position. Left the cap off, filled up the system, started the engine, when the thermostat opened & the coolant level dropped, I topped off the system, filled the overflow tank up about 1/3 & shut everything down. Started it again & let it run a few more minutes, saw the coolant in the overflow bubble a little & knew any remaining air was coming out.

No problems at all!

Randy