I need to flush and refill my coolant and the repair manual I bought at Autozone says I need to remove the drive belt and alternator so I can get at the thermostat and remove it before flushing. However, none of the general flushing instructions I’ve seen online say anything about removing the thermostat so I am wondering whether this is really necessary. I’ve also seen the Prestone coolant flushing kits available ( http://www…20180.html) in which you cut the one of the hoses and install a plastic T-Valve and I am wondering if that would work. Any and all suggestions are welcome! Thanks!
I personally do not like the coolant flushing kits. You’re introducing 3 places for leaks that weren’t there before. And it’s not all that hard to flush coolant without them.
Beyond that, we can’t really give you good advice unless you. . .tell us what car we’re talking about here.
Awww man I can’t believe I forgot that. First post issue I guess 
I have a 2003 Toyota Corolla.
that was my worry with the kit, just more holes.
first determine whether they used pink or red fluid. Whatever they used, use it again. Do not mix the two. Remember that if it’s pink, it’s pre-diluted, so don’t cut it with water.
Now, do you really need to flush it? Have you run it a long time on the current coolant (more than 2-3 year? Or do you know that there is contamination in the fluid (blown head gasket sending oil into the coolant or something?) If not, just drain and refill.
The instruction manual probably says to remove the thermostat because (guessing here, but it’s true for the '05 Corolla) it’s the highest point in the cooling system. Once you get the fluid drained and refill it at the radiator, you’re supposed to top it off through the thermostat hole to get that last bit of air out of the system. You may be able to confirm or deny this by studying that manual you got.
I’ve had the car for a few years (since 05 has a 113k miles) and I’ve never flushed the coolant so I am thinking I am long overdue.
If you don’t have any overheating problems, I’d just drain it from the bottom of your radiator and refill it with a 50/50 mix of coolant and distilled water.
I’ll do that. Thanks!