I'll be doing a coolant flush for the first time on my 2011 fit. This will also be the first time of ever done a coolant flush myself on any car. I had a couple of questions. I watched a youtube video so I have a rough idea of the process.

When I drain the coolant from the petcock how much coolant should drain out?
Do I fill the rad until right before it overflows?
Is there a specific coolant I should be using?
Any hints or tips for someone doing this for the fist time?

Here is the video I watched for the coolant flush and brake fluid flush. The brakes are my next job.

 

I didn't "flush" the coolant on my 2013. Just did a simple drain and fill using Honda Coolant (Honda Long Life Type 2, 1.18 GA (50/50 Mix in jug, no dilute needed). I drained the radiator and emptied the reservoir bottle. I didn't worry with gaining access to the drain bolt to drain the block because it's very difficult and the quantity in the block is very small. I filled the radiator to the top and the reservoir bottle to the MAX line, which pretty much took the entire jug perfectly. No problems.

 

When you drained the rad did you use the petcock?

 

The rad is indeed drained from the petcock!

If you wanna get fancy, you can pull the drain plug in the crankcase also. Radiator fluid shouldn't be contaminated, so there shouldnt be any need to freak out if you dont get all of it, just do your best!

make sure the rad is nice and cool when you take it's hat off. I'm told that them thar big city aluminum radiator types are prone to warping and other stuff if their temps fluctuate too much.

When you pop that radiator cap be sure to look under it for goop, at the fluid for foaming or anything weird. Indicative of serious issues you likely dont have. Little bit of dirt is okay, given that the system is pressurized and steamy, dirt seems to just wind up there.

 

Here is my notes on the procedure:
-->04/06/2019 Changed my coolant (AF-2000 concentrated 1gal + 1gal distilled water). All in all went pretty easy (had my air turned to hot like people said). Drain plug was easy to access (though it took forever to drain). After draining I removed the coolant reservoir (just one 10mm bolt), then I changed the thermostat. A little hard to access here with a hose holder and an angle (two 10mm bolts). Took a little effort but got it, but then the old thermostat was stuck pretty good in there. Pulled it out with pliers then had to clean the mating surface. Then I shot some compressed air hoping to get some more coolant out. More came out when I removed the thermostat than anything. Replaced the drain plug (nothing was wrong with the o-ring), and replaced the reservoir. Filled the radiator with coolant and reservoir, though I overfilled it (likely will fix this eventually). The system overall seems to have taken less coolant than I thought it would. Not really worried about this.

A little different than what you are doing because I also changed the thermostat, but turning your heater on hot and removing the reservoir should be done. Beyond that the guides said to squeeze the big hose to get rid of some air. I must have had very little air in the system because this didn't do much. Only thing that did was running the car with the cap off, which sucked some down and I filled it back up. Basically you can't overfill the radiator, only the reservoir.

 

Yes, nothing to it. Just be sure the system is cool and unscrewing the radiator cap will hasten the drain process.

 

Got it done, thanks for the help guys. One more job done on my fit! Next I gotta do the second part of the transmission flush.

 

After being used to doing e36 BMW cooling systems ( they use a pressurized system that needs to be bled ) I was surprised how easy the Fit was. I had zero issues with air in the system , I got a bit less then a gallon out of the system .

After I drove about 200 miles I put about a splash and a half ( metric ) into the overflow to get it between the lines .