How necessary is it to remove the drain bolt from the RH side of the engine block? I know there's some coolant in the block/heater core, but this bolt--besides being torqued down like a lug nut--is in a position where I can't hardly get any leverage on it. Air box is out of the way, and as the car happened to be due for an oil change, taking off the oil filter gave me a little extra room to slip a socket over the nut. But I can't get a breaker bar in position anywhere, and I can't pull/push hard enough with a socket wrench to break the nut loose. I even tried a MAP torch to encourage that thread sealant and it didn't seem to do any good.

I replaced the upper and lower hoses and installed a new thermostat while I'm at it, so I'd say greater than 2/3 of the coolant is out of the system. And while I hate to contaminate new fluid with old fluid, I just don't see how I can possibly get this nut out. To say nothing of torquing it back down. So what do you guys do? Pull it? Leave it? Whisper sweet nothings at it till it comes out on its own?

 

After draining the radiator until it drips empty, there will be barely any coolant at that drain plug

Not necessary.

 

Even if some old coolant remains, as long as you are using the Honda coolant, you will be fine for the next ten years. If you are really anal about it, fill it up and after some driving for a few days, drain again and refill with fresh. Not needed but you will be pretty sure only 99% of fresh is in there.

I think it is more important to follow Billman's bleed for refilling the coolant to avoid any engine problems of sudden overheating. Read and follow the sticky.

Be sure to keep any brake fluid away from the hoses. Brake fluid and hoses are not good friends. Same goes for paint of course.

 

Hell yeah, that's what I like to hear! It's such a pain where they put it. Other than a complete flush with a hose, I can't imagine why they'd reference it in the service manual

 

If you're worried about leftover coolant, take an air hose and jam it in the bleeder on the fire wall and let her rip. You'll force 99% of the coolant out the radiator drain.

 

Wait, not a garden hose, right? Only use distilled water, not tap water, in radiator. Old school iron blocks didn't care much what water you used. But aluminum blocks care. A lot.

The minerals in tap are not your friend

Also, distilled, like for a clothes iron. Not spring water, which is often right next to it and similarly labeled in grocery store and walmart.

Gallon jug is very cheap.

When I changed my coolant, I just bought premixed coolant, and several distilled water. Drained, filled with distilled, drove around, drained, refilled with genuine Honda premix coolant.

Then Lisle funnel and bleeder screw.

 

I keep putting this off. I need to replace the coolant asap.

 

I changed my coolant when specified and found it appeared to be in perfect shape, at least visually. Very different from the older block cars I did in the past.

 

My car only has just under 25k on the odo but since it is 21 year old coolant I still want to get it changed out. To be fair, the temps have been rock solid since I have owned it.

 

Im due for a change next year, or in 10k miles. Since some evaporates through my silicon hoses I'm always topping it off every 6 months, so I probably got good clean fluid still.