Coolant problems

[Steveb4BMX]

On my Corsa C 1.2 52 plate the collant pipes dont get hot and the heater blow cold. I've replaced the thermostat but unable to remove the air lock. Any ideas thanks Steve.

[Bob69]

Steve, take cap off expansion bottle while engine is cold, then run engine until normal temperature leave for 15-20 mins but keep an eye on coolant level, dont let it get too low, then just add water when needed. This should get rid of the air lock.

[givman2004]

Take thermostat out and run at 3k rpm for a few mins. Gets the water circulating faster then pulling out any air locks and blockages.

Check 2 pipes going into the bulk head are equally warm and the same temp along the entire length. Sometimes the matrix gets blocked stopping the water circulation.