My sister's '92 Civic LX overheated recently, so it's head gasket time (yay!). The coolant and oil mixed big time and left a cruddy film inside the entire cooling circuit. The radiator (the culprit), cap, and thermostat are all being replaced, and the radiator hoses will be washed out by hand. However, what should I do about cleaning out the rest of the circuit. Is there a product I can buy to run through the system once the engine is reassembled, or is a normal water flush enough to clean it out.

Also, how will this affect the system? I don't want to clog up a new radiator or anything like that. Will this substance just re-liquify and drain out, or what?

By the way, I'd imagine this has been covered before, but I tried a couple different search criteria and didn't find anything close. Thanks in advance!

 

Surely someone's been through this and has some input?

 

fill up the colling system with water or coolant

drain the coolant or go to your local shop to get a coolant flush.

refill the cooling system with coolant.

recheck cooling system color a couple of cycles later and see what it looks like.

repeat process until your desired color or mixture is visable. check radiator and not overflow since overflow doesnt circulate well.