Using Airlift UView 5500 question
 

I recently replaced my water pump, thermostat, and front engine mount. I had drained the coolant by removing the hose to the thermostat and waterpump. I put it all back together and added a couple of gallons of FRESH pre-mixed prestone anti-freeze, silicate free, phosphate free, etc. I realize 2 gallons will NOT completely fill the system. I was going to use the Burp method to purge air from system but decided to purchase a UVIEW airlift 5500 system. I have seen the youtube video. I was wondering will it still work if the system is partially filled with coolant? Should I drain what is in the system, use the Airlift system then re-fill again using the Airlift system once it has vacuum?

Yes, you can use the Airlift system on a partially filled system as long as the system is dead cold (zero run time) so you don't create a situation where the coolant starts to boil under vacuum. Just let the system come up to full vacuum (it may burp a bit if there is substantial air pockets in the coolant already on board) and then start flowing in the new mixture.

Any liquid water in the system will boil under a vacuum regardless of the temperature. The good news is that the gas boiling off is primarily water vapor, so you get rid of the air anyway.

I hate to be the bearer of bad news, but the boiling point of pure water under 26 inches of vacuum is about 122 F (http://www.jbind.com/pdf/Cross-Reference-of-Boiling-Temps.pdf..................