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i need to change a cracked expansion tank and so will drain the coolant and replace it as i think that the previous owner was topping it up with neat water for awile.
Does the coolant system need to be bled via screw, or do i simply just drain it at the bottom hose or plug and refill?
Figure i will buy the premixed 50/50 stuff.
Its a 2004 Ford Fiesta 16v 1.25 LX. Ireland.
Thanks
Your Fiesta should have a pressurized recovery tank (plastic tank with yellow cap ... says "Do not open when hot" or some such) ... I'm assuming that's what you're replacing. As long as my assumption is correct, your system is self bleeding. Coolant will travel through your recovery tank, which forces air out of the system. Fill the cooling system up, then start the car. Once you can see coolant flowing through your tank, make sure it is full up to the given lines (high/low). After that, cap the system and run the vehicle, checking the levels right after your drive, then everyday for a week to ensure no trapped air has been found. After that, you should be good to go.
Bleeding is not mandatory but I've found that it's almost always needed after draining and refilling. Very few have "bleed screws" any longer, if yours has one, use it, otherwise you may need to pull the upper line off and "burp" it until enough of the air is out so that it purges itself.
A note on the 50/50 mixes. These cost you at least 2X what the straight stuff costs. You're paying a premium for water.
Buy unmixed coolant and pick up a gallon of distilled water at the grocery on the way home. That stuff is like US$0.50 a gallon. Mix it yourself and save money!
