Drain or Flush Coolant?

Draining the rad is safer then flushing. If you have a lot of dirt or rust in the antifreeze, buy some radiator cleaner from your local auto parts store and let that work for a good 15-20 minutes before you drain the antifreeze out.

Flushing that radiator requires so type of machine or other method of building pressure and forcing the antifreeze out. So if you have minor leaks or worn hoses that you might not have known about, you most likely will notice them after the flush is complete!

Also, flushing may knock dirt or build up from one area and push it into another. This may cause the build up to block the heater core, the thermostat, or even one the of the hoses.

Its better to be safe then sorry. Chances are if you require a flush due to excessive dirt or corrosion, you will need a new rad anyway. If you have normal worn antifreeze in the system now, draining is effective and less risky!

Hope this helps.

Ive drained and refilled my 91 99000m every other year and now have deposits visable looking inside, Im not sure if I should have flushed or drained it better at this point. If you have buildup it needs a chemical and flush, but you can do a low pressure flush im sure machines take this into account and put in 12 lb vs 40- 100 for a hose that could ruin your system, you need a clean system to cool. a 99, replace hoses before they leave you stranded.

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Marc, Have you been using distilled water when you do the refill? It will make a difference not using tap water. davidj92

If you're using only Toyota red coolant and distilled water, and keeping up on it, drain and fill is fine.

This might be a dump question, but where do you get distilled water? Never seen anywhere advertising selling it. Never asked either. I can imagine it might be something very expensive because very few people would buy it.

Thanks!

I always use distilled water, its a 1$ at your grocers, [ but who knows I did not see them distill it] Im suprised I had deposts, some years I did it every year. Im guessing leaving in 1/2 the old it just wore it down faster.

You can buy it in any grocery store. It is no more expensive than cheap bottled drinking water. People buy it to use in their steam irons and other household appliances.

Merritt