I haven't seen a decent DIY for radiator flush, perhaps I haven't looked hard enough. How often do you guys do it? Do you always drain the block? Do you flush with the car running? Problem is keeping the thermostat open when you're pumping in cold water.

 

just drain and replace, there's nothing really need to be flushed if you took care of the cooling system.

using garden hose to "flush" will introduce mineral into the cooling system, depends on your local water quality(something like 20% of water is test in LA), mineral+aluminum = not the best combo

honda OEM ext coolant said to be lasting 100k, I use prestone and swap them out every 25-30k if not sooner(depends on track day)

 

i went to kroger and bought about 4 gallons of distilled water. flushing is not hard, might as well just do it instead of drain replace.

 

There used to be a good one posted by Xviper, but has disappeared. If you have an early model Ap1, it is recommended to do a complete flush if it hasn't been done before. Sometime in the early 00's the fluid was changed and the new isn't compatible with the old.

 

do not flush with water, you have type 2 anti-freeze. mixing with water is a no no

 

A coolant change isn't called for until the maintenance minder calls for a sub item "5" The change interval for 04-05's (which use the same coolant) is 120K or 10 years.

It's not a iron blocked engine, you don't have the dissimilar metal corrosion issues associated with that.

The only thing you'll be flushing from the cooling system is good coolant.

 

I was looking for the same and I have green fluid right now, I know the fluid from honda is pink, should I just flush right away and fill it back up with the one that I got from Honda? No other steps required?

 

The type 2 coolant from Honda is blue, not pink.

 

Green fluid is old fluid (type I). You should do a thorough flush WITH WATER before you move to the new Honda pre-mixed (Type II). Unfortunately, you will always have a little bit of water left after a flush, so the type II will be a little diluted.. I haven't run into problems in three years though.

OP, don't flush your coolant. It's much too soon.. you will just be wasting money.

 

So in order to do a thorough flush, do you have to flush the old fluid, run water in the radiator while keeping the car started for a while so everything is flushed and then turn the water off and then the car off and pour the new one?