any preferred coolant i should use? any recomendations?

 

Any major brand should be ok. For your area, I would recommend about 25-30% coolant. Mix it with distilled water. Don't use tap water. The minerals in tap water are not good for the cooling system.

 

I take it you're flushing it yourself? Cuz if you have the stock AST, and you're getting it pressure flushed like at Jiffy Lube or something of the sort, it'll perforate the seal of the AST.

 

anyone know of a how-to for coolant flushing? never done it myself...

 

http://www.scuderiaciriani.com/rx7/how-to.html

 

To clarify Mahjik's link: there isn't an easy way to do a home flush - unless you put in tap water, and I'll never put tap water in my coolant system, ever. It's basically draining, filling with distilled water, running it, draining it, and putting in coolant. By then you've gotten almost all the old stuff out.

Dave

 

In the cooling system, air is your enemy. Fill slowly, and unplug the coolant hose at the throttle body while filling (be prepared, when it gets nearly full, coolant will start coming out this hose). This will prevent air pockets from forming.

Also, make sure you burp/bleed all the air out of the system. My mechanic friend had a really cool tool, it was like a radiator cap with an overflow tank on top of it. We put this thing on the filler cap, filled it with about 0.75-1.0 L of coolant, and let the engine run for about 5-10 minutes. This released almost 0.25-0.5 L of air bubbles, it was amazing. The tool is there to make sure that when the bubbles come up, coolant is the only thing sucked down into the cooling system.

Good luck,
-scott-

 

That Lightning in a World of Thunder page didn't metion anything about the heater when flushing the system. While youre flushing it, you need to make sure to have your heater on full blast as to make sure that you get all the old coolant out of the heater core as well.

 

here's a question for ya... What's the advantage of flushing it versus just draining it and filling it up with more anti freeze? How do you even know whether your coolant needs draining and or flushing? What are the symptoms? overheating? rough idle? etc?

 

Flushing it will remove gunk more quickly. But most home flush kits simply use water from a hose, which of course isn't distilled (pure). That's why shops have fancier setups to do this whole thing quickly without repeated fills/drains/burps.

But us po folk, we drain/fill/drain/fill a couple of times and save $75. IMO there is nothing wrong with draining and refilling the coolant one time for a couple consecutive oil changes (burping the air out of course) and calling that whole process a 'flush'.

The bottom line is that gunk can accumulate in the cooling system, fouling the transfer of heat a bit and introducing things that can wear the water pump. Or, build up enough concentration to attack coolant hoses chemically (galvanically? - well there was that huge thread about it once). So flush the coolant about every 30k, once a year, twice a year, whatever it is.

Dave

 

so how do you burp the system? the site doesn't say anything about it

 

just have the fill cap off and squeeze the lower radiator hose a few times.