I bought a 187.000 Prius on an CarMax auction and noticed a slime coolant leak on the coolant reservoir. Car at that time already had a burbling sound on the dashboard, wether the heat was on or off and the car was reaching about 96c 206f during hard uphill driving. After looking and tested, found a blown head gasket. Yesterday my friend who works at a hybrid shop was able to install a totally remanufactured cylinder head, with new headgasket, cleaned the EGR, new spark plugs, coils, waterpump(dealer), thermostat , reservoir cap etc. Left the shop with little heat with heater on and the heat started to get back today after start driving, however, the car still getting the burbling sound on the dash despite i drive more than 100 miles with the heater on, monitoring the temperature of course. We believe the last owner used some kind of gasket seal and although we flushed the engine block with a hose could this be the heater core blocked with some gasket seal ? I don't know what do to anymore. Could I do a bypass on the heater core?
There might be a way to do a cooling system flush with something that can dissolve the old sealer. If you are able to get a glob of the old sealer, you could experiment to see what dissolves it.
One sealant manufacturer recommended 50/50 white vinegar and water. there’s a link in my sig, just my thoughts on how to restore system to 50/50 Super Long Life Coolant, after such a flush.
